cathode-ray tube display screens free sample

A cathode-ray tube (CRT) is a vacuum tube containing one or more electron guns, which emit electron beams that are manipulated to display images on a phosphorescent screen.waveforms (oscilloscope), pictures (television set, computer monitor), radar targets, or other phenomena. A CRT on a television set is commonly called a picture tube. CRTs have also been used as memory devices, in which case the screen is not intended to be visible to an observer. The term

In CRT television sets and computer monitors, the entire front area of the tube is scanned repeatedly and systematically in a fixed pattern called a raster. In color devices, an image is produced by controlling the intensity of each of three electron beams, one for each additive primary color (red, green, and blue) with a video signal as a reference.magnetic deflection, using a deflection yoke. Electrostatic deflection is commonly used in oscilloscopes.

Since the mid-late 2000"s, CRTs have been superseded by flat-panel display technologies such as LCD, plasma display, and OLED displays which are cheaper to manufacture and run, as well as significantly lighter and less bulky. Flat-panel displays can also be made in very large sizes whereas 40 in (100 cm) to 45 in (110 cm)

Cathode rays were discovered by Julius Plücker and Johann Wilhelm Hittorf.cathode (negative electrode) which could cast shadows on the glowing wall of the tube, indicating the rays were traveling in straight lines. In 1890, Arthur Schuster demonstrated cathode rays could be deflected by electric fields, and William Crookes showed they could be deflected by magnetic fields. In 1897, J. J. Thomson succeeded in measuring the charge-mass-ratio of cathode rays, showing that they consisted of negatively charged particles smaller than atoms, the first "subatomic particles", which had already been named George Johnstone Stoney in 1891. The earliest version of the CRT was known as the "Braun tube", invented by the German physicist Ferdinand Braun in 1897.cold-cathode diode, a modification of the Crookes tube with a phosphor-coated screen. Braun was the first to conceive the use of a CRT as a display device.

The first cathode-ray tube to use a hot cathode was developed by John Bertrand Johnson (who gave his name to the term Johnson noise) and Harry Weiner Weinhart of Western Electric, and became a commercial product in 1922.

In 1926, Kenjiro Takayanagi demonstrated a CRT television receiver with a mechanical video camera that received images with a 40-line resolution.Philo Farnsworth created a television prototype.Vladimir K. Zworykin.: 84 RCA was granted a trademark for the term (for its cathode-ray tube) in 1932; it voluntarily released the term to the public domain in 1950.

In 1947, the cathode-ray tube amusement device, the earliest known interactive electronic game as well as the first to incorporate a cathode-ray tube screen, was created.

In the mid-2000s, Canon and Sony presented the surface-conduction electron-emitter display and field-emission displays, respectively. They both were flat-panel displays that had one (SED) or several (FED) electron emitters per subpixel in place of electron guns. The electron emitters were placed on a sheet of glass and the electrons were accelerated to a nearby sheet of glass with phosphors using an anode voltage. The electrons were not focused, making each subpixel essentially a flood beam CRT. They were never put into mass production as LCD technology was significantly cheaper, eliminating the market for such displays.

Beginning in the late 90s to the early 2000s, CRTs began to be replaced with LCDs, starting first with computer monitors smaller than 15 inches in size,Hitachi in 2001,Flat-panel displays dropped in price and started significantly displacing cathode-ray tubes in the 2000s. LCD monitor sales began exceeding those of CRTs in 2003–2004

Despite being a mainstay of display technology for decades, CRT-based computer monitors and televisions are now virtually a dead technology. Demand for CRT screens dropped in the late 2000s.

A popular consumer usage of CRTs is for retrogaming. Some games are impossible to play without CRT display hardware, and some games play better. Reasons for this include:

The design of the high voltage power supply in a product using a CRT has an influence in the amount of x-rays emitted by the CRT. The amount of emitted x-rays increases with both higher voltages and currents. If the product such as a TV set uses an unregulated high voltage power supply, meaning that anode and focus voltage go down with increasing electron current when displaying a bright image, the amount of emitted x-rays is as its highest when the CRT is displaying a moderately bright images, since when displaying dark or bright images, the higher anode voltage counteracts the lower electron beam current and vice versa respectively. The high voltage regulator and rectifier vacuum tubes in some old CRT TV sets may also emit x-rays.

Since it is a hot cathode, it is prone to cathode poisoning, which is the formation of a positive ion layer that prevents the cathode from emitting electrons, reducing image brightness significantly or completely and causing focus and intensity to be affected by the frequency of the video signal preventing detailed images from being displayed by the CRT. The positive ions come from leftover air molecules inside the CRT or from the cathode itself

Burn-in is when images are physically "burned" into the screen of the CRT; this occurs due to degradation of the phosphors due to prolonged electron bombardment of the phosphors, and happens when a fixed image or logo is left for too long on the screen, causing it to appear as a "ghost" image or, in severe cases, also when the CRT is off. To counter this, screensavers were used in computers to minimize burn-in.

Various phosphors are available depending upon the needs of the measurement or display application. The brightness, color, and persistence of the illumination depends upon the type of phosphor used on the CRT screen. Phosphors are available with persistences ranging from less than one microsecond to several seconds.

Doming is a phenomenon found on some CRT televisions in which parts of the shadow mask become heated. In televisions that exhibit this behavior, it tends to occur in high-contrast scenes in which there is a largely dark scene with one or more localized bright spots. As the electron beam hits the shadow mask in these areas it heats unevenly. The shadow mask warps due to the heat differences, which causes the electron gun to hit the wrong colored phosphors and incorrect colors to be displayed in the affected area.

Aperture grille screens are brighter since they allow more electrons through, but they require support wires. They are also more resistant to warping.

CRT monitors can still outperform LCD and OLED monitors in input lag, as there is no signal processing between the CRT and the display connector of the monitor, since CRT monitors often use VGA which provides an analog signal that can be fed to a CRT directly. Video cards designed for use with CRTs may have a RAMDAC to generate the analog signals needed by the CRT.multisyncing.

Picture tube CRTs have overscan, meaning the actual edges of the image are not shown; this is deliberate to allow for adjustment variations between CRT TVs, preventing the ragged edges (due to blooming) of the image from being shown on screen. The shadow mask may have grooves that reflect away the electrons that do not hit the screen due to overscan.

A shadow mask tube uses a metal plate with tiny holes, typically in a delta configuration, placed so that the electron beam only illuminates the correct phosphors on the face of the tube;aperture grille of tensioned vertical wires to achieve the same result.

Due to limitations in the dimensional precision with which CRTs can be manufactured economically, it has not been practically possible to build color CRTs in which three electron beams could be aligned to hit phosphors of respective color in acceptable coordination, solely on the basis of the geometric configuration of the electron gun axes and gun aperture positions, shadow mask apertures, etc. The shadow mask ensures that one beam will only hit spots of certain colors of phosphors, but minute variations in physical alignment of the internal parts among individual CRTs will cause variations in the exact alignment of the beams through the shadow mask, allowing some electrons from, for example, the red beam to hit, say, blue phosphors, unless some individual compensation is made for the variance among individual tubes.

The solution to the static convergence and purity problems is a set of color alignment ring magnets installed around the neck of the CRT.magnetic fields parallel to the planes of the magnets, which are perpendicular to the electron gun axes. Often, one ring has two poles, another has 4, and the remaining ring has 6 poles.vector can be fully and freely adjusted (in both direction and magnitude). By rotating a pair of magnets relative to each other, their relative field alignment can be varied, adjusting the effective field strength of the pair. (As they rotate relative to each other, each magnet"s field can be considered to have two opposing components at right angles, and these four components [two each for two magnets] form two pairs, one pair reinforcing each other and the other pair opposing and canceling each other. Rotating away from alignment, the magnets" mutually reinforcing field components decrease as they are traded for increasing opposed, mutually cancelling components.) By rotating a pair of magnets together, preserving the relative angle between them, the direction of their collective magnetic field can be varied. Overall, adjusting all of the convergence/purity magnets allows a finely tuned slight electron beam deflection or lateral offset to be applied, which compensates for minor static convergence and purity errors intrinsic to the uncalibrated tube. Once set, these magnets are usually glued in place, but normally they can be freed and readjusted in the field (e.g. by a TV repair shop) if necessary.

The convergence signal may instead be a sawtooth signal with a slight sine wave appearance, the sine wave part is created using a capacitor in series with each deflection coil. In this case, the convergence signal is used to drive the deflection coils. The sine wave part of the signal causes the electron beam to move more slowly near the edges of the screen. The capacitors used to create the convergence signal are known as the s-capacitors. This type of convergence is necessary due to the high deflection angles and flat screens of many CRT computer monitors. The value of the s-capacitors must be chosen based on the scan rate of the CRT, so multi-syncing monitors must have different sets of s-capacitors, one for each refresh rate.

Dynamic color convergence and purity are one of the main reasons why until late in their history, CRTs were long-necked (deep) and had biaxially curved faces; these geometric design characteristics are necessary for intrinsic passive dynamic color convergence and purity. Only starting around the 1990s did sophisticated active dynamic convergence compensation circuits become available that made short-necked and flat-faced CRTs workable. These active compensation circuits use the deflection yoke to finely adjust beam deflection according to the beam target location. The same techniques (and major circuit components) also make possible the adjustment of display image rotation, skew, and other complex raster geometry parameters through electronics under user control.

Color CRT displays in television sets and computer monitors often have a built-in degaussing (demagnetizing) coil mounted around the perimeter of the CRT face. Upon power-up of the CRT display, the degaussing circuit produces a brief, alternating current through the coil which fades to zero over a few seconds, producing a decaying alternating magnetic field from the coil. This degaussing field is strong enough to remove shadow mask magnetization in most cases, maintaining color purity.deform (bend) the shadow mask, causing a permanent color distortion on the display which looks very similar to a magnetization effect.

Dot pitch defines the maximum resolution of the display, assuming delta-gun CRTs. In these, as the scanned resolution approaches the dot pitch resolution, moiré appears, as the detail being displayed is finer than what the shadow mask can render.

Beam-index tubes, also known as Uniray, Apple CRT or Indextron,Philco to create a color CRT without a shadow mask, eliminating convergence and purity problems, and allowing for shallower CRTs with higher deflection angles.

Flat CRTs are those with a flat screen. Despite having a flat screen, they may not be completely flat, especially on the inside, instead having a greatly increased curvature. A notable exception is the LG Flatron (made by LG.Philips Displays, later LP Displays) which is truly flat on the outside and inside, but has a bonded glass pane on the screen with a tensioned rim band to provide implosion protection. Such completely flat CRTs were first introduced by Zenith in 1986, and used

flat tensioned shadow masks, where the shadow mask is held under tension, providing increased resistance to blooming.TV80, and in many Sony Watchmans were flat in that they were not deep and their front screens were flat, but their electron guns were put to a side of the screen.

Radar CRTs such as the 7JP4 had a circular screen and scanned the beam from the center outwards. The screen often had two colors, often a bright short persistence color that only appeared as the beam scanned the display and a long persistence phosphor afterglow. When the beam strikes the phosphor, the phosphor brightly illuminates, and when the beam leaves, the dimmer long persistence afterglow would remain lit where the beam struck the phosphor, alongside the radar targets that were "written" by the beam, until the beam re-struck the phosphor.

In oscilloscope CRTs, electrostatic deflection is used, rather than the magnetic deflection commonly used with television and other large CRTs. The beam is deflected horizontally by applying an electric field between a pair of plates to its left and right, and vertically by applying an electric field to plates above and below. Televisions use magnetic rather than electrostatic deflection because the deflection plates obstruct the beam when the deflection angle is as large as is required for tubes that are relatively short for their size. Some Oscilloscope CRTs incorporate post deflection anodes (PDAs) that are spiral-shaped to ensure even anode potential across the CRT and operate at up to 15,000 volts. In PDA CRTs the electron beam is deflected before it is accelerated, improving sensitivity and legibility, specially when analyzing voltage pulses with short duty cycles.

When displaying fast one-shot events, the electron beam must deflect very quickly, with few electrons impinging on the screen, leading to a faint or invisible image on the display. Oscilloscope CRTs designed for very fast signals can give a brighter display by passing the electron beam through a micro-channel plate just before it reaches the screen. Through the phenomenon of secondary emission, this plate multiplies the number of electrons reaching the phosphor screen, giving a significant improvement in writing rate (brightness) and improved sensitivity and spot size as well.

Most oscilloscopes have a graticule as part of the visual display, to facilitate measurements. The graticule may be permanently marked inside the face of the CRT, or it may be a transparent external plate made of glass or acrylic plastic. An internal graticule eliminates parallax error, but cannot be changed to accommodate different types of measurements.

Where a single brief event is monitored by an oscilloscope, such an event will be displayed by a conventional tube only while it actually occurs. The use of a long persistence phosphor may allow the image to be observed after the event, but only for a few seconds at best. This limitation can be overcome by the use of a direct view storage cathode-ray tube (storage tube). A storage tube will continue to display the event after it has occurred until such time as it is erased. A storage tube is similar to a conventional tube except that it is equipped with a metal grid coated with a dielectric layer located immediately behind the phosphor screen. An externally applied voltage to the mesh initially ensures that the whole mesh is at a constant potential. This mesh is constantly exposed to a low velocity electron beam from a "flood gun" which operates independently of the main gun. This flood gun is not deflected like the main gun but constantly "illuminates" the whole of the storage mesh. The initial charge on the storage mesh is such as to repel the electrons from the flood gun which are prevented from striking the phosphor screen.

When the main electron gun writes an image to the screen, the energy in the main beam is sufficient to create a "potential relief" on the storage mesh. The areas where this relief is created no longer repel the electrons from the flood gun which now pass through the mesh and illuminate the phosphor screen. Consequently, the image that was briefly traced out by the main gun continues to be displayed after it has occurred. The image can be "erased" by resupplying the external voltage to the mesh restoring its constant potential. The time for which the image can be displayed was limited because, in practice, the flood gun slowly neutralises the charge on the storage mesh. One way of allowing the image to be retained for longer is temporarily to turn off the flood gun. It is then possible for the image to be retained for several days. The majority of storage tubes allow for a lower voltage to be applied to the storage mesh which slowly restores the initial charge state. By varying this voltage a variable persistence is obtained. Turning off the flood gun and the voltage supply to the storage mesh allows such a tube to operate as a conventional oscilloscope tube.

The Williams tube or Williams-Kilburn tube was a cathode-ray tube used to electronically store binary data. It was used in computers of the 1940s as a random-access digital storage device. In contrast to other CRTs in this article, the Williams tube was not a display device, and in fact could not be viewed since a metal plate covered its screen.

In some vacuum tube radio sets, a "Magic Eye" or "Tuning Eye" tube was provided to assist in tuning the receiver. Tuning would be adjusted until the width of a radial shadow was minimized. This was used instead of a more expensive electromechanical meter, which later came to be used on higher-end tuners when transistor sets lacked the high voltage required to drive the device.

Some displays for early computers (those that needed to display more text than was practical using vectors, or that required high speed for photographic output) used Charactron CRTs. These incorporate a perforated metal character mask (stencil), which shapes a wide electron beam to form a character on the screen. The system selects a character on the mask using one set of deflection circuits, but that causes the extruded beam to be aimed off-axis, so a second set of deflection plates has to re-aim the beam so it is headed toward the center of the screen. A third set of plates places the character wherever required. The beam is unblanked (turned on) briefly to draw the character at that position. Graphics could be drawn by selecting the position on the mask corresponding to the code for a space (in practice, they were simply not drawn), which had a small round hole in the center; this effectively disabled the character mask, and the system reverted to regular vector behavior. Charactrons had exceptionally long necks, because of the need for three deflection systems.

Nimo was the trademark of a family of small specialised CRTs manufactured by Industrial Electronic Engineers. These had 10 electron guns which produced electron beams in the form of digits in a manner similar to that of the charactron. The tubes were either simple single-digit displays or more complex 4- or 6- digit displays produced by means of a suitable magnetic deflection system. Having little of the complexities of a standard CRT, the tube required a relatively simple driving circuit, and as the image was projected on the glass face, it provided a much wider viewing angle than competitive types (e.g., nixie tubes).

Flood-beam CRTs are small tubes that are arranged as pixels for large video walls like Jumbotrons. The first screen using this technology (called Diamond Vision by Mitsubishi Electric) was introduced by Mitsubishi Electric for the 1980 Major League Baseball All-Star Game. It differs from a normal CRT in that the electron gun within does not produce a focused controllable beam. Instead, electrons are sprayed in a wide cone across the entire front of the phosphor screen, basically making each unit act as a single light bulb.light-emitting diode displays. Unfocused and undeflected CRTs were used as grid-controlled stroboscope lamps since 1958.Electron-stimulated luminescence (ESL) lamps, which use the same operating principle, were released in 2011.

In the late 1990s and early 2000s Philips Research Laboratories experimented with a type of thin CRT known as the Zeus display, which contained CRT-like functionality in a flat-panel display.

Some CRT manufacturers, both LG.Philips Displays (later LP Displays) and Samsung SDI, innovated CRT technology by creating a slimmer tube. Slimmer CRT had the trade names Superslim,

At low refresh rates (60 Hz and below), the periodic scanning of the display may produce a flicker that some people perceive more easily than others, especially when viewed with peripheral vision. Flicker is commonly associated with CRT as most televisions run at 50 Hz (PAL) or 60 Hz (NTSC), although there are some 100 Hz PAL televisions that are flicker-free. Typically only low-end monitors run at such low frequencies, with most computer monitors supporting at least 75 Hz and high-end monitors capable of 100 Hz or more to eliminate any perception of flicker.sonar or radar may have long persistence phosphor and are thus flicker free. If the persistence is too long on a video display, moving images will be blurred.

This problem does not occur on 100/120 Hz TVs and on non-CGA (Color Graphics Adapter) computer displays, because they use much higher horizontal scanning frequencies that produce sound which is inaudible to humans (22 kHz to over 100 kHz).

High vacuum inside glass-walled cathode-ray tubes permits electron beams to fly freely—without colliding into molecules of air or other gas. If the glass is damaged, atmospheric pressure can collapse the vacuum tube into dangerous fragments which accelerate inward and then spray at high speed in all directions. Although modern cathode-ray tubes used in televisions and computer displays have epoxy-bonded face-plates or other measures to prevent shattering of the envelope, CRTs must be handled carefully to avoid personal injury.

Under some circumstances, the signal radiated from the electron guns, scanning circuitry, and associated wiring of a CRT can be captured remotely and used to reconstruct what is shown on the CRT using a process called Van Eck phreaking.TEMPEST shielding can mitigate this effect. Such radiation of a potentially exploitable signal, however, occurs also with other display technologies

As electronic waste, CRTs are considered one of the hardest types to recycle.phosphors, both of which are necessary for the display. There are several companies in the United States that charge a small fee to collect CRTs, then subsidize their labor by selling the harvested copper, wire, and printed circuit boards. The United States Environmental Protection Agency (EPA) includes discarded CRT monitors in its category of "hazardous household waste"

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Global Cathode Ray Tube Display Market, By Type (Curved Screen, and Others), Application (Television Screens, Desktop Computer Monitors, Wireless Phone and Portable IT Devices, Commercial and Industrial), End User (Electronics, Automotive, and Consumer Goods) – Industry Trends and Forecast to 2029

Cathode ray tube display (CRT) are being widely used in PC gaming circles as they deliver high pixel resolution, are suitable for use in both dimly lit and dark environments. CRT displays are being preferred as they create perfectly smooth gray scale with an infinite number of intensity levels, and are less expensive.

Global Cathode Ray Tube Display Market was valued at USD 729.19 million in 2021 and is expected to reach USD 1225.05 million by 2029, registering a CAGR of 6.70% during the forecast period of 2022-2029. Electronics accounts for the largest end user segment in the respective market owing to the rapid digitization. The market report curated by the Data Bridge Market Research team includes in-depth expert analysis, import/export analysis, pricing analysis, production consumption analysis, and pestle analysis.

Cathode ray tube (CRT) refer to the displays that use CRT. This technology is a vacuum tube medium that interprets electrical phenomenon of an image projected on a phosphorescentscreen. The interpretation is done by sharp focused beam of electrons being generally controlled by an intensity of electrical signals.

Type (Curved Screen, and Others), Application (Television Screens, Desktop Computer Monitors, Wireless Phone and Portable IT Devices, Commercial and Industrial), End User (Electronics, Automotive, and Consumer Goods)

Toshiba Corporation. (Japan), Panasonic Corporation (Japan), Koninklijke Philips N.V. (Netherlands), Schneider Electric (France), Siemens (Germany), Mitsubishi Electric Corporation (Japan), SONY INDIA. (India), and Chunghwa Picture Tubes, LTD. (Taiwan), among others

Increase in the use of Cathode ray tube display (CRT) in customer electronics across the globe acts as one of the major factors driving the growth of cathode ray tube display market. Also, rise in the adoption of these displays owing to reduction in display costs.

The increase in the usage of consumer electronics display devices along with reduced display costs further influence the market. Also, constant upgrade in display technology assist in the expansion of the market.

Additionally, rapid urbanization, change in lifestyle, surge in investments and increased consumer spending positively impact the cathode ray tube display market.

Furthermore, advancements in the cathode ray tube display technology extend profitable opportunities to the market players in the forecast period of 2022 to 2029. Also, surge in investments will further expand the market.

On the other hand, high cost associated with the manufacturing is expected to obstruct market growth. Also, lack of awareness and low refresh rate are projected to challenge the cathode ray tube display market in the forecast period of 2022-2029.

This cathode ray tube display market report provides details of new recent developments, trade regulations, import-export analysis, production analysis, value chain optimization, market share, impact of domestic and localized market players, analyses opportunities in terms of emerging revenue pockets, changes in market regulations, strategic market growth analysis, market size, category market growths, application niches and dominance, product approvals, product launches, geographic expansions, technological innovations in the market. To gain more info on cathode ray tube display market contact Data Bridge Market Research for an Analyst Brief, our team will help you take an informed market decision to achieve market growth.

The COVID-19 has impacted cathode ray tube display market. The limited investment costs and lack of employees hampered sales and production of cathode ray tube display technology. However, government and market key players adopted new safety measures for developing the practices. The advancements in the technology escalated the sales rate of cathode ray tube display as it targeted the right audience. The increase in sales of devices such as consumer electronics across the globe is expected to further drive the market growth in the post-pandemic scenario.

The cathode ray tube display market is segmented on the basis of type, application and end user. The growth amongst these segments will help you analyze meager growth segments in the industries and provide the users with a valuable market overview and market insights to help them make strategic decisions for identifying core market applications.

The cathode ray tube display market is analyzed and market size insights and trends are provided by country, type, application and end user as referenced above.

The countries covered in the cathode ray tube display market report are U.S., Canada, Mexico, Brazil, Argentina, Rest of South America, Germany, Italy, U.K., France, Spain, Netherlands, Belgium, Switzerland, Turkey, Russia, Rest of Europe, Japan, China, India, South Korea, Australia, Singapore, Malaysia, Thailand, Indonesia, Philippines, Rest of Asia-Pacific, Saudi Arabia, U.A.E, South Africa, Egypt, Israel, Rest of Middle East and Africa (MEA).

North America dominates the cathode ray tube display market because of the introduction of advanced technology along with rising disposable income of the people within the region.

The cathode ray tube display market competitive landscape provides details by competitor. Details included are company overview, company financials, revenue generated, market potential, investment in research and development, new market initiatives, global presence, production sites and facilities, production capacities, company strengths and weaknesses, product launch, product width and breadth, application dominance. The above data points provided are only related to the companies" focus related to cathode ray tube display market.

Unless you’ve been following the less mainstream tech conversations going on these days, you might have missed a renewed discussion on the merits of CRT or cathode ray tube screens. Yes, we’re talking about the original ‘tube’ that has now been all but replaced by various flat panel technologies.

Believe it or not, there’s an entire generation of people who have probably never seen a CRT in real life! So why are people in tech circles talking about this older technology today? What are CRT monitors used for? Isn’t modern display tech superior?

One of the biggest drawbacks of flat panel screens is that they have a “native” resolution. In other words, they have a fixed, physical grid of picture elements. So a full HD panel has 1920 by 1080 pixels. If you send an image with a lower resolution to such a panel, it has to be scaled so that multiple physical pixels act as a single virtual pixel.

Still, images on a CRT look good at any resolution. This is because there are no physical pixels using this display technology. The image is drawn on the inside of the screen using electron beams, so no scaling is required. The pixels are simply drawn at the size they need to be. So even relatively low resolution images look nice and smooth on a CRT.

LCD flat panels use a display method known as “sample and hold”, where the current frame stays on screen in a perfectly static way until the next one is ready. CRTs (and plasma screens) use a pulsed method. The frame is drawn on screen, but immediately begins to fade to black as the phosphors lose energy.

Modern screens either use some form of “motion smoothing”, which leads to the dreaded “soap opera effect” or they insert black frames between the regular ones which causes brightness reduction. CRTs can show sharp motion with no brightness sacrifice and can therefore look much better when playing back video.

Due to the way LCDs work, it’s essentially impossible to display true black in an image. An LCD panel consists of the LCD itself, with its array of color-changing pixels and a backlight. Without the backlight, you won’t see the image. That’s because LCDs don’t give off any light of their own.

The problem is that when a pixel switches off to display black, it doesn’t block all the light coming from behind it. So the best you can get is a sort of grey tone. Modern LCD screens are much better at compensating for this, with multiple LEDs evenly lighting the panel and local backlight dimming, but true blacks are still not possible.

CRTs on the other hand can display blacks almost perfectly thanks to how it draws the picture on the back of the screen. Modern technologies like OLED does nearly as well, but is still far too expensive for mainstream consumers. Plasma was also very good in this regard, but has been largely phased out. So right now in 2019 the best black levels are still to be found in CRTs.

While there are plenty of ways in which CRTs are objectively superior to even the best modern flat panel displays, there’s also a long list of cons! After all, there’s a reason the world moved to newer display technology.

It’s also important to remember that flat panel displays at the time of the shift were far worse than those of today, yet people felt the pros of LCDs were on balance a better deal.

CRT screens are huge, heavy, power-hungry and less suitable for productivity and watching widescreen films. While their resolution limits aren’t a huge issue for video games, any sort of serious work turns into struggle with low resolution text and a lack of desktop real estate.

It"s true. Running modern games on a vintage CRT monitor produces absolutely outstanding results - subjectively superior to anything from the LCD era, up to and including the latest OLED displays. Best suited for PC players, getting an optimal CRT set-up isn"t easy, and prices vary dramatically, but the results can be simply phenomenal.

The advantages of CRT technology over modern flat panels are well-documented. CRTs do not operate from a fixed pixel grid in the way an LCD does - instead three "guns" beam light directly onto the tube. So there"s no upscaling blur and no need to run at any specific native resolution as such. On lower resolutions, you may notice "scan lines" more readily, but the fact is that even lower resolution game outputs like 1024x768 or 1280x960 can look wonderful. Of course, higher-end CRTs can input and process higher resolutions, but the main takeaway here is that liberation from a set native resolution is a gamechanger - why spend so many GPU resources on the amount of pixels drawn when you can concentrate on quality instead without having to worry about upscale blurring?

Then there"s display lag, or rather, the complete lack of it. Imagery is beamed directly onto the screen at the speed of light, meaning zero delay. Even compared to 240Hz LCDs I"ve tested, the classic mouse pointer response test feels different, faster. The advantages in terms of game response - particularly with an input mechanism as precise as the mouse - need no further explanation.

On a more general level, there"s a sense that games and hardware have "grown" into CRT technology over the years. Visuals are more realistic than they"ve ever been, and there"s something about the look of a CRT presentation that further emphasises that realism - aliasing in particular is much less of an issue compared to a fixed pixel grid LCD. Secondly, PC hardware has evolved now to the point where running at higher refresh rates than 60Hz is relatively simple - and a great many CRT monitors can easily run at much faster frequencies, up to 160Hz and even beyond, depending on the display and the input resolution. This is all pretty good for a technology that essentially became obsolete soon after the turn of the millenium.

And that"s where the negatives of CRT gaming start to hit home. The technology is outdated, which presents many pitfalls. The most obvious concerns form-factor: CRT displays are big, bulky and weigh a lot. I invested in a display widely considered to be one of the greatest CRTs ever made - the Sony Trinitron FW900 - a 16:10 24-inch screen. As the video hopefully demonstrates, picture quality is immense, but so is the heft of the screen. It weighs 42kg and with a 600x550mm footprint, the amount of real estate required is not insignificant.

Then there"s the input situation. CRT monitors use VGA, DVI-I or component RGB BNC inputs - and pretty much the most powerful modern GPU still to offer support there is the GTX 980 Ti or Titan X Maxwell. Thankfully HDMI, USB-C and DisplayPort to VGA adapters are available, but you"ll be spending a lot of time online looking for the right one to handle high pixel-rates if you intend to go past 1920x1200 at 60Hz. Very few widescreen CRTs are available and even the Sony FW900 has a 16:10 aspect ratio, meaning that console gaming isn"t really a good fit for CRT displays - 4:3 screens, even less so. Yes, you can run consoles on a CRT, but my feeling is that for many reasons, this is a pursuit best suited to PC users.

Finally, there"s the cost - which can cut both ways - along with the quality of the display you"ll actually get. The FW900 is a legendary screen with massive asking prices to match. However, John Linneman"s 19-inch 4:3 Sony Trinitron G400 cost him just 10 Euros (!) and still looks amazing. However, the fact is that in both John"s case and mine, the screens weren"t in optimal condition when we bought them - which is to be expected for screens well into their second decade of life. Suffice to say, getting image quality to the expected levels can take a lot of time, effort and plenty of research. And on a more basic level, CRT screens are made of glass and glare can be an issue. In shooting the video on this page, I had to film at night in order to show the screen in the best possible light.

There are plenty of pitfalls then - but the end results while gaming are highly satisfactory. Modern titles on a CRT can look sensational, you have the benefits of high refresh rates if you want them, you can turn up all the eye candy and you don"t need to worry so much about resolution as a major defining factor of image quality. Today"s premium-priced gaming LCDs are trying very hard to recapture CRT"s major benefits - low latency, high refresh rates and reduced input lag - but as good as many of these screens are, for our money nothing beats a good old-fashioned cathode ray tube display for desktop gaming - not even the very best LCD screens on the market.

Color CRT monitors use a phosphor-coated screen. Phosphors are arranged in strips and emit visible light when exposed to an electron beam generated within the CRT. Three beams are used in CRT monitors to excite red, green, and blue color in combinations needed to create the various hues that form the picture. CRT monitors are gradually being replaced by LCD flat panel monitors in households and offices. The light emitting mechanism of LCD monitors is different than that of CRTs. LCD displays use two basic techniques for producing color: passive matrix or thin film transistor. Basically, LCD monitors utilize two sheets of polarizing material with a segmented liquid crystal solution between them. An electric current passes through the liquid causing the crystals to align so that the light emission of individual pixels can be controlled. LCD monitors are typically backlit by a white light fluorescent (fluorescent-backlit) or LED light (LED-backlit) source since the liquid crystals generate no light of their own.

For many decades, conventional film-screen systems have been the tools of choice for diagnostic procedures. Although a cathode-ray tube (CRT) monitor is relatively expensive and has limited spatial resolution and luminance compared to conventional film, computed radiographic technology can produce image quality that is adequate for interpreting posteroanterior radiographs of the chest, while offering the advantages of gray-scale manipulation and flexible image-processing. It is well accepted that the diagnostic performance of a CRT monitor is sufficient to replace conventional radiographs (12, 13); however, constant operation causes CRTs to degrade and to lose beam focus, spatial linearity, luminance, uniformity, brightness, and contrast. In addition, due to their high initial purchase price and the high maintenance expenditure needed for correction and calibration, CRT monitors are costly. They are, furthermore, not only heavy and bulky but also have high levels of heat dissipation and power consumption. In contrast, high-resolution liquid crystal display (LCD) monitors provide clear, cost-effective and energy-efficient display. The significant advantage of an LCD monitor is the consistency of image display throughout its lifecycle, and the absence of degradation over time. The luminance of an LCD monitor is high enough to locate the flat panel next to conventional medical light boxes, and its additional benefits include a slim and compact profile and the fact that it emits no low-level radiation.

Our results indicate that for the display and analysis of soft-copy images in the detection of a solitary pulmonary nodule, LCD and CRT monitors are comparable, but when interpreting our results, several considerations should be borne in mind. First, the LCD monitor was operated at a higher brightness level (700 cd/m2) than the CRT monitor (490 cd/m2), and this might have made the LCD results appear more favorable than they really were. Nonetheless, since the brightness of both monitor systems was set according to the recommendation of the suppliers, we believe that our results reflect real clinical practice. Second, in terms of contrast and focus, the LCD monitor is superior to the CRT monitor (14), so the former is less sensitive to ambient light. Even though all the reading sessions in our study were performed in a dark room, environmental light could influence image contrast during a CRT session. Third, the matrix number of the imaging plates used in this study was 1760×2140, which is similar to the resolution of the LCD monitor, with a matrix of 1536×2048. In addition, the detection of a pulmonary nodule is more dependent on contrast than spatial resolution, and so in our study, the superiority of the CRT monitor in terms of spatial resolution might not be an advantage. Fourth, despite the other merits of the CRT monitor, including less angle viewing dependence and far fewer artifacts, we considered that these factors did not influence visual comparisons between the LCD and CRT display when used to detect a solitary pulmonary nodule.

Pavlicek et al. (15) showed that compared with CRT monitors, LCD monitors have higher luminance and a shorter warm-up time, but the two types are of comparable uniformity, and are fully acceptable for clinical image viewing. However, they did not study their diagnostic performance, measuring only their display performance at actual clinical locations and administering a user questionnaire. A study by Siegel, presented at the American Roentgen Ray Society meeting on April 30, 2002, found no significant differences in overall sensitivity and specificity between LCD and CRT monitors used for the detection of pulmonary nodules on chest radiographs. Siegel did not, however, use receiver-operating-characteristic analysis to compare diagnostic performance between the two types of monitor, and to our knowledge, ours is the first study to use ROC analysis to compare the two types in terms of their ability to diagnose solitary pulmonary nodules. This study was designed to simulate daily clinical practice; readers used a commercial PACS viewer, and real-time adjustment of contrast and brightness, the most commonly used functions in daily practice, was allowed.

In conclusion, for the display of soft-copy digital images, LCD monitors and CRT monitors are comparable, and for the detection of small solitary non-calcified pulmonary nodules in medical practice, LCD monitors are acceptable replacements for the cathode-ray type.

Our results showed that the mfERGs elicited by a stimulus array created on an OLED screen were comparable to the mfERGs elicited by a stimulus array created on a CRT screen. No significant difference was observed between the P1 amplitude of the first- and second-order kernels elicited by the OLED from that elicited by the CRT whereas the P1 amplitude of the first-order kernel elicited by the LCD stimuli was significantly smaller than that elicited by the CRT in all the groups of the averaged hexagonal elements. Only a few implicit times—the N1 implicit time from rings 2, 4, and 5 and the P1 implicit time from ring 5—were significantly different between the CRT and OLED monitors. In contrast, the N1, P1, and N2 implicit times of the first-order kernels were delayed in the mfERG elicited by the LCD in all of the rings compared to the mfERGs recorded elicited by the CRT screen. These findings indicate that the OLED screens would be better for creating stimuli to elicit mfERGs.

The use of OLED screens has expanded although there are still difficulties in producing large-size OLED screens, and their relatively high cost limits their use for television screens and computer monitors. Because OLED displays do not have a backlight, their black is blacker than that of LCD screens. Under low ambient conditions, an OLED screen can have a higher contrast than CRT and LCD screens. OLEDs also have the advantage of a faster response time than standard LCD screens. The LCD displays are capable of between 1 and 16 ms response times leading to a refresh rate of 60 to 480 Hz; however, an OLED can theoretically have less than a 0.01-ms response time enabling a refresh rate of up to 100,000 Hz. Thus, OLEDs can also be used as a flicker stimulus similar to CRTs.

The photosensor measurements showed that the luminance changes of the OLED and CRT screens were very rapid and not significantly different (Figure 4). However, the luminance changes were basically different, i.e., rectangular for the OLED and a train of bursts in CRT. The practical usefulness of these two screens can be confirmed by using them for mfERG recordings as used in routine clinical settings.

The characteristics of OLED screens have been evaluated in detail (Cooper, Jiang, Vildavski, Farrell, & Norcia, 2013; Elze, Taylor, & Bex, 2013; Ito, Ogawa, & Sunaga, 2013), and our results are in good agreement with these earlier evaluations. Recently, the characteristics of an OLED screen (Sony PVM-2541, 24.5-in.; Sony Corporation, Tokyo, Japan) have been precisely measured from the viewpoint of its applicability to visual psychophysics (Cooper et al., 2013). The tested OLED screen was reported to have excellent luminance and color uniformity; excellent low-luminance gradation; stable white and three primary colors throughout the wide luminance range; wide color space, especially for saturated green; and rapid luminance rise/fall times. The authors stated that if large enough OLED displays were constructed, it would be ideal for vision research. However, they also stated that the concept of one frame in the PVM-2541 is different from those in an LCD or CRT display, and it is unclear whether these differences will affect the human perception of short-duration stimuli.

The luminance changes in the LCDs had a relatively slow rise from black to white and slow fall from white to black. Our previous experiments (Matsumoto et al., 2013) showed that the time delay caused a transient reduction in the averaged luminance of the entire display. To reduce the transient reduction, either decreasing the contrast of the checkerboards or using higher frequency–driven LCDs would be effective. But such a setup for the LCD screen is not easy when used in clinical practice.

When examining each component of the mfERGs, the amplitude of P1 of the first-order kernel and the amplitude of P2 of the second-order kernel elicited by an LCD screen were significantly different from those elicited by a CRT. Only the P1 amplitudes in all rings and the P2 amplitudes in rings 1 and 2 of the second-order kernel were identical between the waves elicited by the LCD and CRT screens. In addition, the implicit times of all components in all of the rings were significantly delayed when the LCD was used as a stimulator compared to that when the CRT was used. This is in good accord with the results by Kaltwasser, Horn, Kremers, and Juenemann (2009) who investigated the suitability of LCD as a visual stimulator for mfERGs. They stated that when an LCD screen was used as a stimulator, the increase in the implicit times and differences in the luminance-versus-time profile must be taken into account. Most of the LCD screens have similar properties with slow luminance rises and falls. The drive system of the LCD display used in this paper was vertical alignment (VA). This system has some advantages by having more uniform luminances and deeper black with a high contrast ratio than twisted nematic (TN) panels. The disadvantage is that they have a slower response time compared to TN panels. In the manufacturer"s specifications of the LCD monitor, the response speed is reported to be 25 ms for black-white-black, which is relatively slow. We measured the rise (black to white, 10% to 90% luminance) and fall times (white to black, 90% to 10% luminance), and the results were 6.2 and 9.6 ms, respectively (Supplemental Figure 2).

We believe that the differences of the response times, rise and fall times, and durations of the on-luminance between LCD and CRT screens were the cause of the significant differences in the values of the different components of the mfERGs obtained by the LCD as opposed to those elicited by CRT screens.

The fusion of the LCD responses implies that the m-sequences underlying the multifocal technique cannot be accurately reproduced by the LCD display. Therefore, further investigations on LCD screens with a 120-Hz refresh rate and/or inserting a black frame after each stimulus frame may be helpful to solve this. In other words, our results demonstrated that no black frames are necessary with OLEDs because no fusion occurred.

The long input lag observed in the OLED is unlikely due to the OLED itself but may be due to the Sony BKM229X RGB/Component video input module signal conversion that we used to convey the analog video signal from the VERIS mfERG system for the digital display. Our results that OLED showed negligible response time is in accordance with the results of Cooper et al. (2013). However, our results differed from theirs in that they did not evaluate the effect of input lag. This is because they used the voltage change from the photodiode placed on the monitor, so the recording was triggered by the luminance change of the monitor whereas our results showed long input lag, probably due to the video module signal conversion used in this study.

There are several limitations in this study. The frequency used was not 75 Hz, which is widely used in clinical practice. The mechanism for the differences in the implicit times between mfERGs recorded using different monitors was not determined. The properties of the luminance changes were different, and their influence on the retinal response was unknown. Investigating the influence of the different properties on the human visual system will be interesting, but we have only investigated the possibility of substituting the CRT monitor with another monitor as a visual stimulator for mfERG. We investigated a single LCD and a single OLED monitor, but the input lag and response time are unique in LCD and OLED screens. Therefore, a better LCD screen or a better OLED monitor as a visual stimulator may be found with further investigations. Moreover, we only used the S1721 Flexscan LCD monitor, which is a VA type LCD. A TN LCD, which has 5 ms of response time, may minimize the overlapping and may show similar results as OLED displays. In the literature of Cooper et al. (2013), the LG Flatron D2342 LCD, one of the TN LCDs, shows increasing slope up to 5 ms and, after that, shows a plateau (saturation) response. However, most TN LCD panels have a disadvantage in that their response time increased markedly when used under a special mode, such as fine color drawing or low-contrast conditions. Further investigations are needed to compare commercially available TN LCDs with CRTs as visual stimulators to elicit mfERGs.

In conclusion, an OLED screen is a better substitute for a CRT screen on which to create stimuli to elicit mfERGs. Although the waveforms of the mfERGs are similar, they are not completely identical. We recommend that normative mfERGs elicited by OLED screens be collected from normal eyes before the mfERGs from diseased eyes are examined.

CRT stands for Cathode Ray Tube. CRT is a technology used in traditional computer monitors and televisions. The image on CRT display is created by firing electrons from the back of the tube of phosphorus located towards the front of the screen.

A cathode ray tube (CRT) is the glass video display component of an electronic device (usually a television or computer monitor). EPA encourages repair and reuse as a responsible ways to manage CRTs. If reuse or repair are not practical options, CRTs can be recycled. Recycled CRTs are typically disassembled so that valuable materials can be recovered.