CN116953988A - Device for improving chromaticity stability of LED - Google Patents

Abstract

The invention discloses a device for improving the chromaticity stability of an LED, which comprises an LED lamp, an LED backlight plate and a diffuse reflection film, wherein the diffuse reflection film is cut into different shapes and shields a part of luminous surfaces of the LED lamp; the brightness of the product is obviously reduced, the application range is wider, and the method is applicable to both direct type and side-entry type backlight liquid crystal displays, and can meet the design requirement of the display product under the low-brightness use condition. On the premise of meeting the low-brightness index of the product, the LED can still work under the nominal working current, the chromaticity stability of the LED under the working state is greatly improved, and the display quality of the product is improved.

Description

A device for improving LED color stability

Technical field

The invention relates to the field of display devices, and in particular to a device for improving LED chromaticity stability.

Background technique

At present, LCD monitors occupy most of the market in the display industry. LCD monitors are an electronic display terminal product. They are mainly composed of LCD panels, backlights, structural parts, circuit control boards, etc. Liquid crystal display is a passive display technology that requires a backlight system to provide a light source to complete the display. Currently, the light source in the LCD industry mainly uses LED inorganic light-emitting diodes.

In the application of LCD displays, it is generally necessary to add a brightness adjustment function to improve the comfort of use under different ambient illumination. The brightness adjustment function is achieved by controlling the current flowing through the LED lamp through the LED drive circuit or controlling the "bright and dark" time ratio of the LED.

The core of the LED inorganic light-emitting diode is a III-IV compound in the periodic table of elements. It is excited by applying a positive voltage to produce optical radiation. In addition to being affected by the type of raw materials selected, the chromaticity characteristics of the light emitted are also affected by the flow through the The current value of the chip also has a great relationship.

The current method for determining chromaticity characteristics in the LED industry is to make the LED lamp work at a specified current, test its chromaticity characteristics, and use them as the chromaticity characteristics of the LED, and put LEDs with the same chromaticity characteristics into the same bin area ; However, in actual product applications, in order to meet the low-brightness display requirements of some products, LEDs often need to be driven with a current value below the specified current value. At this time, the chromaticity characteristics of the LED lamp at low current values are different from those of the manufacturer. The factory-calibrated values vary greatly, and the chromaticity of LEDs in the same bin area may even be inconsistent, resulting in poor product display.

Contents of the invention

The purpose of the present invention is to provide a device for improving LED chromaticity stability, which can achieve low brightness indicators without reducing the LED operating current, and flexibly match the shape of the diffuse reflection film according to the low brightness indicators of the product, which can both It ensures that the LED works at the nominal current and meets the low brightness requirements of the product.

A device for improving LED chromaticity stability, including LED lamps, LED backlight panels and diffuse reflection films;

The LED lights are installed on the front of the LED backlight panel;

The diffuse reflection film is attached to the LED backlight panel;

The diffuse reflection film is cut into different shapes and covers part of the light-emitting surface of the LED lamp.

Preferably, the cutting size of the diffuse reflection film needs to be calculated through the following steps:

Step 1: Test the luminous flux of the LED lamp under the nominal operating current, calculated as Alm;

Step 2: According to the low brightness index requirements of the product, calculate the luminous flux required by the product, calculated as Blm;

Step 3: Assume that the size of the cutting hole in the diffuse reflection film is am ² and the luminous area of the LED lamp itself is BM ² , so that the exposed luminous area of the LED lamp is reduced, and the reduction ratio complies with the required luminous flux and the nominal luminous flux ratio formula.

Preferably, the ratio formula between the required luminous flux and the nominal luminous flux is:

1-(ba/b) ² =A/B.

Preferably, the diffuse reflection film can be cut into different shapes by a laser cutting machine.

The advantages of the present invention are: 1. The effect of reducing product brightness is obvious, and the scope of application is wide. It is suitable for both direct-type and side-type backlight LCD displays, and can meet the design requirements of display products under low-brightness usage conditions.

2. On the premise of meeting the low brightness indicator of the product, it can be ensured that the LED is still working at the nominal working current, which greatly improves the chromaticity stability of the LED in this working state and improves the display quality of the product.

Description of the drawings

Figure 1 is a schematic diagram of the diffuse reflective film shielding the LED light-emitting surface of the present invention;

Figure 2 is a schematic diagram of conventional diffuse reflective film application;

Figure 3 is an example of the relationship between LED chromaticity characteristics and current;

01. LED light, 02. LED backlight, 03. Diffuse reflective film.

Detailed ways

In order to make the technical means, creative features, objectives and effects achieved by the present invention easy to understand, the present invention will be further elaborated below in conjunction with specific implementation modes.

As shown in Figures 1 to 3, the present invention includes an LED lamp 01, an LED backlight plate 02 and a diffuse reflection film 03;

The LED lamp 01 is installed on the front of the LED backlight panel 02;

The diffuse reflection film 03 is attached to the LED backlight panel 02;

The diffuse reflection film 03 is cut into different shapes and blocks a part of the light-emitting surface of the LED lamp 01 .

The cutting size of the diffuse reflection film 03 needs to be calculated through the following steps:

Step 1: Test the luminous flux of LED lamp 01 under the nominal operating current, calculated as Alm;

Step 2: According to the low brightness index requirements of the product, calculate the luminous flux required by the product, calculated as Blm;

Step 3: Suppose the size of the cutting hole in the diffuse reflection film 03 is am ² , and the luminous area of the LED lamp 01 itself is BM ² , so that the exposed luminous area of the LED lamp 01 is reduced, and the reduction ratio is consistent with the ratio of the required luminous flux and the nominal luminous flux. formula.

The ratio formula between the required luminous flux and the nominal luminous flux is:

1-(ba/b) ² =A/B.

The diffuse reflection film can be cut into different shapes by a laser cutting machine.

Specific implementation methods and principles:

The present invention consists of a diffuse reflection film 03. The diffuse reflection film 03 can be cut into different shapes using a laser cutting machine and pasted on the LED backlight plate 02 to improve the efficiency of the backlight system. The present invention reduces the size of the holes cut in the diffuse reflection film. The diffuse reflection film 03 is cut by laser so that the diffuse reflection film 03 covers part of the LED lamp 01 and the light-emitting surface of the LED lamp 01, so that the emitted luminous flux of the LED lamp 01 is smaller than the luminous flux of the LED itself, as shown in Figure 1. In the figure, only LED light 01 is used. Expose the middle 2/3 part.

Conventional diffuse reflection film cutting is to cut holes of corresponding sizes according to the package size of the LED. After pasting, the entire LED light-emitting surface will be exposed, and the emitted luminous flux of the LED is equal to the luminous flux of the LED itself, as shown in Figure 2.

The present invention first needs to test the luminous flux of the LED light panel under the nominal operating current, which is calculated as Alm.

According to the low brightness index requirements of the product, calculate the luminous flux required by the product and calculate it as Blm.

The size of the cut holes in the diffuse reflection film is calculated as am ² and the LED's own luminous area is calculated as bm ² , so that the exposed luminous area of the LED is reduced, and the reduction ratio is consistent with the ratio of the required luminous flux and the nominal luminous flux, such as the formula:

1-(ba/b) ² =A/B

The invention avoids the problem of LED chromaticity shift in low-brightness products, and can achieve a low-brightness indicator without reducing the LED operating current. The device shape is flexibly matched according to the low brightness index of the product, which can not only ensure that the LED operates at the nominal current, but also meet the low brightness requirements of the product.

Based on the above, the present invention has an obvious effect of reducing product brightness and has a wide range of applications. It is applicable to both direct-type and side-type backlight LCD displays, and can meet the design requirements of display products under low-brightness usage conditions. Under the premise of meeting the low brightness indicator of the product, it is ensured that the LED is still working at the nominal operating current, which greatly improves the chromaticity stability of the LED in this working state and improves the display quality of the product.

It is known from common technical knowledge that the present invention can be implemented by other embodiments without departing from its spirit or essential characteristics. Therefore, the above-disclosed embodiments are in all respects illustrative and not exclusive. All changes within the scope of the present invention or within the scope equivalent to the present invention are included in the present invention.

Claims (4)

1. The device for improving the chromaticity stability of the LED is characterized by comprising an LED lamp (01), an LED backlight plate (02) and a diffuse reflection film (03);

the LED lamp (01) is arranged on the front surface of the LED backlight plate (02);

the diffuse reflection film (03) is adhered to the LED backlight plate (02);

the diffuse reflection film (03) is cut into different shapes and shields a part of the light emitting surface of the LED lamp (01).

2. The device for improving chromaticity stability of LEDs as recited in claim 1, wherein: the cut size of the diffuse reflection film (03) needs to be calculated by the following steps:

step one: the luminous flux of the LED lamp (01) under the nominal working current is tested and is counted as Alm;

step two: calculating the luminous flux required by the product according to the low brightness index requirement of the product, wherein the luminous flux is Blm;

step three: setting the size of the cutting hole of the diffuse reflection film (03) as am ² The self luminous area of the LED lamp (01) is bm ² The exposed light emitting area of the LED lamp (01) is reduced, and the reduced proportion accords with a required luminous flux and nominal luminous flux proportion formula.

3. The device for improving chromaticity stability of LEDs as recited in claim 2, wherein: the formula of the ratio of the required luminous flux to the nominal luminous flux is as follows:

1-(b-a/b) ² ＝A/B。

4. the device for improving chromaticity stability of LEDs as recited in claim 1, wherein: the diffuse reflection film (03) can be cut into different shapes by a laser cutter.