The LED display was widely used in our daily life, you can see LED display application everywhere, on the road, home appliance, motorcycle … etc. Beside this LED display, there are some advance technology , For Example, MicroLED ,MiniLED and OLED, that have similar structure.

The LED Display’s Characteristic

The LED display’s structure is sample and can easily meet outdoor requirement in brightness and emitting color by change LED current and LED material. In addition to ,The epoxy-base LED display assembly make it easy to pass the high reliability test to outdoor application.The price for standard type LED display is not too high, normally to be used for traffic light, thermal meter display, indicator for home appliance, count down meter…..etc.

The NRE (Non-recurring engineering Expense) cost for custom display (ex. Special size, height, involve more components, special color…etc.) is much lower than LCD/Mini LED/Micro LED, especially for the irregular shape & size. Reader can see this article about full customization tooling cost for LED display.

Generally speaking, to custom a LED display, Opto Plus requests a US$3,000 – 6,000 tooling cost according to the overall design.

The Structure Of The LED Display

Depending on the structure, the LED display can be divided into two types:

• LED display without reflective cover.

• LED display with reflective cover.

LED Display Structure (Without Reflective Cover)

The LED display structure without reflective cover is divided into three parts:

• Dot matrix display cover

• Light Emitting Diode (LED)

• Printed Circuit Board (PCB)

Take the common traffic signal display (little green man display) on the road as an example, the traffic signal display is made of dot matrix display cover (Dot matrix display), the upper display of the countdown number and red light stop sign, the lower display of the little green man walking animation, the light emitting diode (LED Lamp) assembled on the printed circuit board (PCB) that has make the circuit, the LED switch control, the production of digital and small green man animation applied to the traffic signal display (Little Green Man monitor) on.

Most large LED displays use architectures that do not include reflective covers to reduce costs. In addition, in recent years, MiniLED and MicroLED, which have been very compacted, are also LED displays without reflective covers if they are used for display purposes instead of backlight modules, but the size and spacing of LEDs are reduced to millimeters (Millimeter, mm) and microns (Micrometer, μm) levels.

LED Display Structure (With Reflective Cover)

• Light Emitting Diode (LED)

• Printed Circuit Board (PCB)

• Reflective Cover

Take the common floor display in the elevator as an example, the floor display is made of dot matrix display (Dot matrix display), the combined icons such as the upper left corner icon, the lower is the internal approximate structure diagram, the light emitting diode (LED) is assembled on the printed circuit board (PCB) that has been made of the circuit, through the upper reflective cover (Reflective Cover), to produce a uniform, will not interfere with each other Light points, arranged into the shape of the matrix, Applied on elevator floor displays.

This article will focus on the introduction of LED displays that contain reflective covers, such as Seven segment display，Alphanumeric display，Dot matrix display，and Bar graph display。

Structure of an LED display containing a reflective cover – An example is given using the internal structure of the Dot matrix display displayed on the elevator floor.

The Type Of LED Display

The DISPLAY means to display the Words, Pictures, it can be classified to 4 types:

1. Words.
2. A certain picture.
3. Limited words +certain pictures.
4. Any pictures.

Type Of LED Display– 7 Segment Display

     The main structure for 7 segment display is 7 segment emitting area & 1 right bottom emitting area.  Therefore, why we call it “7 segment display” or “8 number display” (when all segment light up, it is a 8 number) or even call “numeric display” (display number).     Most of 7 segment display have a right bottom side emitting area, we call it DP point (Data point).     Opto Plus LED Corp. defines each emitting segment clockwise from A segment to G segment & DP point.  Please refer to Data Sheet for OPS-S4010SE-GW as below:

     If you want know more about 7-Segment display about internal structure and details. Please see “Introduce each kind of 7-segment display, 16-segment display , and Internal structure!“. If you want know how 7-Segment display information like Arabic Numerals  or English Alphabet. You can refer to this article “How to display Numerals and English Alphabet in 7-segment and 16-segment LED display?” article.if you want to protect your LED display with a limited current resistor, you can refer to this article “How to design a 7 segment display with limited current resistor? “ .

Type Of LED Display– Alphanumeric Display

Alphanumeric display is a complicate 7 segment display, specially design to display the numbers 0-9 and the English Letters A-Z. Alphanumeric display have similar naming rules in 7 segment display. To perform all English letters in capital & low cases letters, the main emitting segment numbers have 3 kind design (9 segment, 14 segment, 16 segment):

1. 9 emitting segment – Nine segment display
2. 14 emitting segment – Fourteen segment display
3. 16 emitting segment – Sixteen segment display.

     The most popular alphanumeric display is sixteen segment display.Same as 7 Segment display, Opto Plus LED Corp. defines each emitting segment by A segment to P segment & DP point.  Please refer to Data Sheet for OPD-AS8020(1)LA-GW as below:

     If you want know more about 16-Segment display about internal structure and details. Please see “Introduce each kind of 7-segment display, 16-segment display , and Internal structure!“. If you want know how 16-Segment display information like Arabic Numerals  or English Alphabet. You can refer to this article “How to display Numerals and English Alphabet in 7-segment and 16-segment LED display?” article.if you want to protect your LED display with a limited current resistor, you can refer to this article “How to design a 7 segment display with limited current resistor? “ .

Type Of LED Display– Icon/Bar Display

   Use the pictures to display the information is very common application in home appliance products. Moreover, to use light bar to display the rate of progress is very easy & intuition way. The advantage for using pictures & bar can overcome the different languages to be used all the world.     Below are 2 example products to present Icon (pictures) + Bar + 7 segment display (OPS-V32)  & Light Bar display (OPS-B500LA-UT-GW). The OPS-V32 is a very typical custom display combined with 7 segment + icon (pictures) + Bar for customer display purpose. OPS-B500LA-UT-GW can be connect more than 1 display together to meet customer requirements.

OPS-V32

Type Of LED Display– Mix-Type Display

Most of mix type display is customize display to meet customer’s special application – might be very big size, irregular appearance or very small size, or very thin size. For example, the Dash Board display like Gogoro 2 Plus is a typical Mix-Type display, this display involves all below function and make the Dash board more fashion, availability, functionality, colorful & activity performance.

1. Big size, irregular appearance.
2. Huge 7 Segment to display the Speed of motorcycle.
3. Function pictures to display direction light, ABS, IOS…etc.
4. Bar to present battery volume.
5. RGB color circumstances light.

Type Of LED Display– Dot Matrix Display

LED dot matrix is to using the emitting dot to display the pictures or letters (all languages), can be classify to (display limited information) & (display any information), please refer to below introduction:

Dot Matrix Display– To Display Limited Information

The most typical application is the numbering indicator for traffic light, this kind of display is just be designed to display limited information.For example, the top light was designed to (only) can display 2 yellow numbers for count down function & the red little men is to prohibit to walk. The bottom light is a Walking Green Little Men when the top light is in count down model. This is using a mono color LED’s emitting light to perform the dot matrix function to display limited information. Normally, it is used for big size application, and use DIP/THT LED mono color lamp or SMD LED to perform Dot matrix function. The cost is lower.

Dot Matrix Display– Can Display Any Information

Most of mono color or full color moving sign is belong to this type display.Below photos is the LED moving sign structure made by 96pc 8*8 LED dot matrix display OPD-M58810W-GW

　　 If you want know more about dot matrix display about internal structure and details. Please see “Introduce dot matrix display’s name, type, internal structure, and application scene“. If you want know how dot matrix display information like Arabic Numerals ,English Alphabet ( at least 3*5 dot to display a English Alphabet or Arabic Numerals , the most populer format is 5*7 dot /characters ) and Traditional Chinese (at least 16*16 dot to display a Chinese characters , you can display more detail in 64*64 dot) . You can refer to this article “Explain how dot matrix display digits, English letter, and pixelated graphic?” article.

The Difference Between LCD Display, LED Display, OLED ,Mini-LED & Micro-LED.

　　 There are two mainstream display in the market – LCD display and LED display. Most of TV or Screen made by LCD technology to express complex information. Traditional LED display like 7-segment LED display , dot matrix LED display are widely use in home appliance, dashboard display that display simple information like digit or icon. LED display made by OLED, Mini-LED & Micro-LED technology to express complex information have more advantage than LCD display in brightness and contrast. On the other hand, LCD display’s price were cheaper to these LED display due to a much mature mass production technology.

　　 Traditional LED display ,OLED , Mini-LED and Micro-LED were made by similar technology with different scale and color mixing method .In this article, We try to explain with these two points of view .

Use Proportion Chart To Understand What’s The Major Difference In Traditional LED Display, Mini-LED And Micro-LED.

     Basic idea is use single color chips in a area to perform all information & pictures.Use OPTO PLUS Standard dot matrix LED display OPD-M21610(1)LR-GW as a example to explain the difference between traditional LED display to Mini-LED / Micro-LED display.The dot size for a LED display and the spacing between the dot usually call dot diameter and pitch,For Mini-LED / Micro-LED / LCD display are pixel and pixel pitch. A main difference between LED display , Mini-LED / Micro-LED or LCD display is the size of the dot. For OPD-M21610(1)LR-GW,A the 12 x 12 Dot Matrix LED display present 144 dot with 1.9 (mm) dot diameter and 2.54 (mm) pitch. The OPD-M21610(1)LR-GW outline dimension and light up GIF show as below.

　　 As we mention earlier, The difference LED Display and MiniLED/MicroLED major in scale. Following Table and picture show the size difference.

　　 In order to demo the scale difference between these display, We use arrange three display side by side as following picture to show the size difference.

The Advantage To Use MicroLED/ MiniLED/ OLED Display To Replace LCD display

1. As small pixel as better to perform high resolution display. So, the MicroLED/ MiniLED/ OLED can perform better resolution than LCD display.
2. The MicroLED/ MiniLED/ OLED display is self emitting light, but LCD display is using a back light through a conduct light board to perform different colors. So, the MicroLED/MiniLED can react quickly and the color contrast better than LCD. Is’s hard for a LCD display to achieve TureDark , On the other hand, the self emitting light characteristic for MicroLED/ MiniLED/ OLED make it easy to achieve TureDark and better image quality.
3. The MicroLED/ MiniLED/ OLED display is more save energy than LCD display.
4. However, the yield rate for MicroLED & MiniLED is still no good. Hard to be mass production.The price is too high for the market.