negative lcd display free sample

LCD (Liquid Crystal Displays) have two options or display modes.Positive mode (dark characters on a light colored background) and negative mode (lighter colored characters on a darker background).

Please see Fig.1: Yellow green STN (Super Twisted Nematic) display, the background of yellow green is lighter than dark blue characters. It is a positive mode. Fig. 2 is a blue STN display, its background of blue is darker than the white characters.It is negative mode.

Positive mode displays have the advantage of their lighter background and no backlights are needed. They normally use transflective or reflective polarizers and have lower power consumption. They can be seen with ambient light.

Negative mode displays need backlit in order to be seen. They normally use transmissive polarizers. They have better contrast and wider viewing angles in the indoor dim environment. The readability is much better than positive displays.

But under bright ambient light or even under direct sunlight, the displays will be easily washed out. In order to be seen under the bright surrounding light, the backlight brightness has to be increased to over 800 nits. The sunlight readable displays consume much power.

Of course, we can always use LED backlight in the LCD module with fewer LED chips and turn off LED backlight when not use to save power. When can also add transflective polarizer to some negative LCDs to make it sunlight readable, but the contrast will be compromised.

Positive and negative mode concept is not only limited to monochrome LCD displays (LCD panels, character LCDs, graphic LCDs etc.), it also uses for color displays, or even other display technologies.  We will categorize the displays as below,

Character LCD modules (Alphanumeric LCD display modules) with character sets: 8×1 LCD display, 8×2 LCD display, 16×1 LCD display, 16×2 LCD display, 16×4 LCD display, 20×2 LCD display, 20×4 LCD display, 24×2 LCD display, 40×2 LCD display, 40×4 LCD display. COB (Chip on Board) bonded, 4 or 8 bits parallel, SPI, I2C interface

Graphic LCD modules with dot matrix sets 122×32, graphic LCD display, 128×64 graphic LCD display, 192×48 graphic LCD display,192×64 graphic LCD display,240×64 graphic LCD display,240×128 graphic LCD display,240×160 graphic LCD display with different color LED backlights, with COB and COG (Chip on Glass) assembling technologies

Monochrome and Color Graphic OLED modules with dot matrix sets 128×32 graphic OLED display,128×64 graphic OLED display, 128×96 graphic OLED display, 160×128 graphic OLED display, 128×128 graphic OLED display, 256×65 graphic OLED display

Full Color TN and IPS displays with panel sizes: 1.3”IPS display, 1.44” TN display, 1.5” IPS display, 1.77”TN and IPS displays, 2.0” TN and IPS displays, 2.2” IPS display, 2.35” IPS display, 2.4” TN and IPS displays, 2.8” TN and IPS displays, 3.5” TN and IPS displays, 4.3” TN display, 5.0” TN and IPS display, 7.0” TN and IPS display, 10.1” IPS display with medium and high brightness (sunlight readable), with parallel, SPI, RGB, LVDS, MIPI interfaces.

NHD-C12864WO-B1TTI#-M | Monochrome Graphic COG | 128x64 Pixels | White Pixels on Black Background | White Backlight | FSTN (-) Negative Display | Mounting Holes | Non-Stocked

Newhaven 128x64 graphic Chip-On-Glass (COG) Liquid Crystal Display shows white pixels on black background. This transmissive LCD Display requires a backlight for visibility and offers a wide operating temperature range from -20 to 70 degrees Celsius. This NHD-C12864WO-B1TTI#-M display includes mounting holes. It has an optimal view of 6:00, operates at 3.3V supply voltage and is RoHS compliant.

Easily modify any connectors on your display to meet your application’s requirements. Our engineers are able to perform soldering for pin headers, boxed headers, right angle headers, and any other connectors your display may require.

Choose from a wide selection of interface options or talk to our experts to select the best one for your project. We can incorporate HDMI, USB, SPI, VGA and more into your display to achieve your design goals.

Newhaven 16x2 character Liquid Crystal Display shows characters with bright pixels on a black background. The RGB display includes three backlight colors built into each display, which enables you to choose from a red, green or a blue backlight color. You can also mix the intensities of those colors to create new custom colors. This transmissive LCD Display requires a backlight for visibility while offering a wide operating temperature range from -20 to 70 degrees Celsius. This NHD-0216K1Z-NS(RGB)-FBW-rev1 display has an optimal view of 6:00, operates at 5V supply voltage and is RoHS compliant.

Easily modify any connectors on your display to meet your application’s requirements. Our engineers are able to perform soldering for pin headers, boxed headers, right angle headers, and any other connectors your display may require.

Choose from a wide selection of interface options or talk to our experts to select the best one for your project. We can incorporate HDMI, USB, SPI, VGA and more into your display to achieve your design goals.

As we know, LCD screen is a negative display which can’t emit light on its own. It either relies on ambient light or uses LED backlight in the back as a light source. We divide LCD screen intotransmissive LCD, reflective LCD, and transflective LCDaccording to the employing mode of light. Also, we divide LCD screen into the positive display and negative display according to the light of the background part.

It is very simple, but most people can’t fully understand the meaning. We already introduced the difference between TN, HTN, STN and FSTN LCD in my previous post. The offset angle of liquid crystal in TN LCD is 90 degrees. What is that? If we see TN, HTN, STN and FSTN LCD in the perspective of view angle, it is much easier for us to understand.

Normally, it would be 6:00 o’clock direction or 12:00 o’clock direction. 6:00 o’clock direction means that we can see it clearly from the frontage and 6:00 o’clock direction. We can still see it clear from 3:00 or 9:00 o’clock direction if we make it well enough even it is 6:00 o’clock direction. The digital clock display in a car is installed on the right-hand side of the driver, which is usually 9:00 o’clock direction.

For example: if the view direction of TN LCD is 6:00 o’clock direction, you will see the graphic very blurred at any angle of 3:00 o’clock or 9:00 o’clock direction. We can still see it clearly within 20 degrees of 3:00 o’clock or 9:00 o’clock direction if it is 6:00 o’clock direction HTN LCD.

As we all know, A liquid crystal display is a passive display, it cannot emit light and can only use ambient light. It requires very little energy to display patterns or characters. It is precise because of low power consumption and miniaturization that LCD has become a better display method.

The liquid crystal material used in liquid crystal display is an organic substance with both liquid and solid properties. Its rod-like structure is generally arranged in parallel in the liquid crystal cell, but its arrangement direction can be changed under the action of an electric field.

For positive TN-LCD, when no voltage is applied to the electrodes, the LCD is in the “OFF” state, and light can pass through the LCD to be in a white state; when a voltage is applied to the electrodes, the LCD is in the “ON” state, and the long axis direction of the liquid crystal molecules is in the “OFF” state. Aligned along the direction of the electric field, light cannot pass through the LCD and is in a black state. By selectively applying a voltage to the electrodes, different patterns can be displayed.

For negative STN-LCD, the twist angle of the liquid crystal is larger, so the contrast ratio is better and the viewing angle is wider. STN-LCD is displayed based on the principle of birefringence. Its primary color is generally yellow-green, and the font is blue, which becomes a yellow-green mode. When using a violet polarizer, the base color will turn gray into a gray mold. When using a polarizer with a compensation film, the base color will become close to white. At this time, STN becomes a black and white mode, which is FSTN. The polarizer of the above three modes is turned 90°, which becomes a blue mode, and the effect will be better.

Whatever TN LCD/STN screen, they usually have two display types: positive display type and negative display type. Today, I am going to use segment display and PMOLED display as examples to show you the differences between positive and negative liquid crystal displays.

As shown above, the bottom is gray and white/green, the characters are black, and the color of the characters should be darker than the background color, that is, a positive display;

There is also a relatively simple way of distinguishing, that is, the color of most of the positive display characters is black. I just mentioned that this type of screen has a good display effect in the sun. It is precisely because the characters are black, so the direct sunlight is not easily affected under the conditions.

As shown in Figure 2 above, the bottom is black/blue, the words are white, and the color of the words is lighter than the background, which is a negative display;

There is also a relatively simple way to distinguish, that is, the color of most of the negative display characters is white, because the LCD screen itself does not emit light, the color of the negative display characters is actually the color printed by the backlight through the glass, and the backlight is white. The typed word is also white, in other words, the negative display must have a backlight to display the content.

1. Positive display: It is white (the natural color of the LCD screen) with black numbers and letters on the bottom, that is, dark characters on a light-colored background. Such as black characters on a yellow/green background (yellow/green screen), and black characters on a gray-white background.

2. Negative display: It is a black background, and the numbers and letters are displayed in white (the natural color of the LCD screen), that is, light-colored characters on a dark background. Such as white text on a blue background, and white text on a black background.

AMOLED is a full-color display, it can support both positive and negative displays. PMOLED display can only support Negative display because of the characteristics of the Passive OLED.

negative lcd display provide the touch interface in smartphones, which are vital for them to function. Alibaba.com stocks a stunning range of high-tech negative lcd display with vibrant color depictions. Truly crystal-clear displays of negative lcd display are available covering various brands and models such as the Samsung Galaxy Edge 2, OnePlus 7T, Samsung Galaxy C5, and many more.

negative lcd display are the most commonly used displays, as they produce great image quality while consuming low power. Rather than emitting light directly, they use back lights or reflectors to produce images, which allows for easy readability even under direct sunlight. negative lcd display are energy-efficient, and are comparatively safer to dispose of, than CRTs. negative lcd display are much more efficient when it comes to usage in battery-powered electronic equipment, due to their minimal power consumption.

Some other advantages of negative lcd display over the CRT counterparts are - sharper images, little to no heat emission, unaffected by magnetic fields, narrow frame borders, and extreme compactness, which make them very thin and light. Some types of negative lcd display are transmissive, reflective, and transflective displays. Transmissive displays provide better image quality in the presence of low or medium-light, while reflective displays work best in the presence of bright light. The third type of negative lcd display, transflective, combine the best features of both the other types and provide a well-balanced display.

Whether as an individual purchaser, supplier or wholesaler, browse for an extensive spectrum of negative lcd display at Alibaba.com if you don"t want to stretch a dollar yet find the best fit.

The LCD2S-204BIW is a Serial LCD Character Display Module with a high speed SPI/I2C serial bus. The LCD display is a 4x20 character, STN blue (negative), white LED backlight, and is RoHS compliant. A LCD2S-2042 is soldered onto the back of the LCD display. It enables the LCD display to be controlled via an I2C or SPI serial bus. The contrast and backlight are software controlled, and can be set to 254 levels.

The LCD2S-204 includes a 4x4 (16 button) matrix keypad encoder with software debouncing. A keypad with up to 16 buttons (4 rows by 4 columns) can be added to the display via a standard 10 pin, 2.54mm header. Our 12 button or 16 button keypads can be used, and can be connected to the LCD2S-204 via the CAB16RIB150 ribbon cable. When using the I2C serial bus, an interrupt line will be activated when a key is pressed, informing the user that there is key data to be read. Alternatively the LCD2S-204 can be polled to see if it has any pending keypad data.

The LCD2S-204 also has 5 user configurable, general purpose inputs/outputs. Two of them can deliver up to 1000mA each, and have protection circuitry for driving relays.

The LCD used must supports 4 bit mode. All 20x4 Character Modules sold on our site support 4 bit mode, and nearly all commercially available LCD Character Modules support it too. The LCD2S-204 has a high speed SPI/I2C serial bus. For convenience the I2C and SPI signals are available via a Micro Match type connector, and a standard 2.54mm, 2x6 row pin header. Most new Modtronix SBC boards have Micro Match connectors, and can be connected to the LCD2S-204 using these 150mm or 300mm cables. Or, the conn-micmat6-MW Micro Match connector can be used to create a custom cable.

The LCD2S has 2 general purpose open collector outputs, OUT1 and OUT2. These outputs can supply up to 1000mA, and have protection circuitry for driving relays. Both OUT1 and OUT2 are enabled by default. They are available via the X3 connector (2x6 pin header).

A matrix keypad supporting up to 16 buttons (4x4 matrix) can be connected to the LCD2S-162. The keypad is connected to the pins marked R1 to R4 (rows) and C1 to C4 (columns) on the X1 1x10 pin header. The LCD2S has built in button debouncing, which can be configured for different values. The default should work fine though.

The picture on the right shows and example of connecting a 12 button keypad, relay and buzzer to the LCD2S. The buzzer can be configured to sound each time a button is pressed, or controlled via the OUT command.

An import function allows additionally to use Windows fonts. With the FontEditor it is easy to generate for example Cyrillic, Greek and Arabic fonts. The preview function shows immediately the size and style in simulation window. When the testboard EA 9780-2USB is connected to the USB port, you can see the character (or any predefined text) live on the display which is plugged-in!

As the saying goes, a picture is worth a thousand words... so to illustrate the differences between the positive mode LCD and negative mode LCD see the image below.

Positive mode LCD means that the letters/characters are dark colored and the background color is light. This mode of LCD will operate with and without a backlight.

Negative mode LCD means that the letter/characters are light colored and the background is dark. Negative mode LCD’s must have a backlight ON to operate.

We offer three types of monochrome LCD’s: Character LCD, Graphic LCD and Segment (Static) LCD. All three of these displays can operate in both negative and positive mode. Any of the three types of displays above can run in negative mode for TN, STN and FSTN.

Static displays do not normally contain a backlight. If you wish to use this type of display in negative mode, please notify us that you will need a backlight. Many times the backlight for a static display may need to be customized.Focus displays offers Character LCD modules (aka alphanumeric LCD display or LCD monochrome display) in the following configurations: 8x1 LCD display, 8x2 LCD display, 16x1 LCD display, 16x2 LCD display, 16x4 LCD display, 20x2 LCD display, 20x4 LCD display, 24x2 LCD display, 40x1 LCD display, 40x2 LCD display, 40x4 LCD display.

Focus displays offers Segment LCD Displays (aka static displays glass and numeric LCD displays) in the following configurations: 7 (seven) segment LCD display, 14(fourteen) segment LCD display, 16(sixteen) segment LCD display,

Liquid crystal displays (LCDs) are comprised of tiny elements of color called pixels. Pixels have dimensions of a few microns or less and consist of three subpixels colored red, green, and blue. The popular acronym, RGB, is often used to delineate the color of a specific pixel within 16.7 million different color combinations. These tiny pixels are densely packed into television screens, computer monitors, tablets, and phones that utilize backlighting to illuminate each pixels and create the complex patterns we recognize as graphics and images today.

Figure 2:The six primary components of an liquid crystal display: 1. polarizing film, 2. electrode, 3. liquid crystal layer, 4. second electrode, 5. second polarizing film, 6. mirror or backlight. Image courtesy of Wikipedia under GNU Free Documentation License.

The most important concept in LCD technology is the behavior of liquid crystals. A twisted nematic liquid crystal layer acts to rotate (twist) the plane of polarization to align or misalign with the second polarizer. This means that if the polarizers are 90 degrees apart (see Figure 3, 4), then the twisted crystals will align with the second polarizer and permit light to pass through. Conversely, if the crystal layer did not exist, light would not pass through because the polarizers are oriented in such a way that the second polarizer blocks the light from the first polarizer.

Electrodes in LCDs function as on and off switches. The electrodes tune their voltage from on to off in 256 increments for each RGB subpixel. This is what gives 16.7 million different colors for each pixel (3 pixels, each with 256 shades; 2 raised to the 24th power).

In more primitive LCDs like those in digital watches or calculators, mirrors are used to reflect natural light to produce the digits we see on the displays. For more modern, high-power screens like TVs and laptops, backlights are used to illuminate the pixels. The backlights are often rectangles or strips of flourescent lamps or light emitting diodes (LEDs).

The most elementary concept of a computer screen lies in the manipulation of light. The goal here was to provide a simple overview of the primary components of a liquid crystal display (LCD) and its deceptive mechanics. Often, LCDs are thought of as complex systems not worth understanding, when in reality, an LCD consists most primitively of six parts: two polarizers, two electrodes, a liquid crystal layer, and a backlight or mirror. Once these mechanisms are understood, the complexity of a LCD remains in the deception of the human eye - not in the nature of its physics.