JP7043277B2 - Light source module and backlight device - Google Patents

Description

The present invention relates to a backlight device and a display device provided with a light source module that divides an area and individually adjusts the brightness.

Since the luminous efficiency of LEDs has improved in recent years, three types of LEDs that emit three primary colors, red (R), green (G), and blue (B), are used in backlights for liquid crystals and the like. It has become. A method of obtaining white light by mixing RGB light emitted from these three types of LEDs has come to be used.

However, it is known as a prior art that the rate of change in brightness with energization time varies greatly depending on the type of LED (the "type" of the LED means a type classified according to the emission color (emission wavelength)). (See Patent Document 1).

The reason is that the LED generates heat when the LED is energized to emit light, and the luminous efficiency of the LED itself decreases due to the heat generation, but the rate of decrease differs depending on the type of LED. Further, when the LED is energized for a long time, the LED deteriorates, and the deterioration rate also differs depending on the type of LED.

In this way, since the rate of change in brightness differs depending on the type of LED, even if each brightness is adjusted to emit white light at the time of initial setting, the ratio of each brightness changes as it is used. .. Therefore, the mixed light will show a hue deviating from white.

It is preferable to solve these problems so that stable white light can be emitted. For example, a light receiving element that receives white light obtained by mixing the three primary colors of RGB and measures the light energy of each wavelength band of RGB, and an adjusting means that adjusts the light energy of the light source based on the signal of the light receiving element. A lighting device equipped with the above has been developed (see Patent Document 1).

On the other hand, as the size of the liquid crystal panel increases, the amount of light becomes insufficient in the backlight using the light guide plate (so-called edge light type backlight). Therefore, a backlight (so-called direct type backlight) is required in which a light source module in which a plurality of LEDs are arranged on a substrate is arranged on the back surface of the liquid crystal panel and the light is directly irradiated from the back surface of the liquid crystal panel.

Similar to other light sources using LEDs, the direct type backlight also has variations in white light unless the amount of LED light is adjusted as needed due to differences in emission intensity, temperature characteristics, aging deterioration, etc. depending on the type of LED. Will occur.

Even if each light source module is adjusted so as to emit good white light in the manufacturing stage of the light source module constituting the direct type backlight, the following problems occur. Specifically, when these light source modules are incorporated inside the device, the color varies from light source module to light source module due to the temperature distribution inside the device. Further, when each light source module is energized, the substrate temperature rises with the passage of energization time due to the self-heating of the LED, so that the increase in the substrate temperature also causes color variation. Further, when the LED is used for a long time, the degree of deterioration differs depending on the type of LED, which causes color variation.

Therefore, even if each light source module is adjusted at the manufacturing stage, it is necessary to appropriately correct the amount of light for each type of LED mounted on the light source module while using the light source module.

Therefore, as a conventional technique, the same number of RGB LEDs of each color are arranged so as to be distributed almost uniformly in each light source module, and the light receiving element is arranged in the center thereof to measure the state of the light taken out from the light source module. It is known (see Patent Document 2).

Japanese Unexamined Patent Publication No. 2004-253309 (published on September 9, 2004) Japanese Unexamined Patent Publication No. 2007-214053 (published on August 23, 2007)

However, in the above-mentioned conventional technique, arranging the same number of LEDs of each color of RGB in the light source module so as to disperse them substantially uniformly, and further arranging the light receiving elements is troublesome and reduces the production efficiency. There is. Further, since only one light receiving element is arranged in the center of the backlight device, there is a problem that the deterioration degree of each LED in the light source module cannot be evaluated and fine correction cannot be performed.

One aspect of the present invention is to realize a backlight device including a light source module that divides an area and individually adjusts the brightness.

In order to solve the above problems, the light source module according to one aspect of the present invention includes a light emitting element, a light receiving element, and a transparent resin, and the light emitting element and the light receiving element are assembled in the same package. It is characterized in that the light emitting element and the light receiving element are packaged so as to be protected by a transparent resin.

According to one aspect of the present invention, it is possible to provide a light source module that individually adjusts the brightness in the backlight device.

It is a schematic diagram of the LED module with a built-in light receiving element which concerns on Embodiment 1 of this invention. It is a schematic diagram of the matrix arrangement which concerns on Embodiment 1 of this invention. It is a schematic diagram of the matrix arrangement which concerns on Embodiments 2 and 3 of this invention. It is a schematic diagram of the switching circuit which concerns on Embodiment 4 of this invention. It is the schematic of the common LED module which concerns on Embodiment 5 of this invention. It is a schematic diagram of the matrix arrangement which concerns on Embodiments 4 and 5 of this invention.

[Embodiment 1]
Hereinafter, one embodiment of the present invention will be described in detail.

[Structure of LED module 10 with built-in light receiving element]
FIG. 1 is a schematic view showing a configuration example of the LED module 10 with a built-in light receiving element according to the present embodiment. In the LED module 10 with a built-in light receiving element, one LED unit 30 and one light receiving element 40 composed of LEDs of each color of red (R), green (G), and blue (B) are arranged as light emitting elements, and they are the same. A light source module assembled in a package and covered with resin 20. In a preferred embodiment, it is packaged as a light source module so as to be protected by a transparent resin.

[Action of LED module 10 with built-in light receiving element]
The light receiving element 40 in the module detects light from the LED unit 30 composed of three types of LEDs that emit light of the three primary colors red (R), green (G), and blue (B), respectively. The resin 20 protects the LED module 10 having a built-in light receiving element and facilitates handling, and also has a role of a lens that diffuses the light emission of the LED.

[Backlight device configuration using only the LED module 10 with a built-in light receiving element]
FIG. 2 shows an aspect of the backlight 200 in which the plurality of LED modules 10 with built-in light receiving elements of FIG. 1 are arranged in a matrix on one surface of a substrate. Although FIG. 2 shows a 6 × 6 matrix sequence, any numerical value can be adopted as the sequence mode. In a preferred embodiment, the LED control circuit (not shown) is arranged on a surface opposite to the surface of the substrate on which the LED module 10 with a built-in light receiving element is arranged. In a preferred embodiment, the LED control circuit includes, in addition to the LED drive circuit (not shown), a module control circuit (not shown) that receives the value of the light receiving element 40 and corrects the LED drive current to correct the brightness. Be prepared.

By arranging the LED modules 10 having a built-in light receiving element in this way, it is not necessary to separately arrange the LED and the light receiving element as in the prior art (Patent Document 2), and it is possible to improve the efficiency of substrate production.

Since the LED module 10 with a built-in light-receiving element shown in FIG. 2 can measure the brightness of the self-luminous LED unit 30 with the light-receiving element 40 in the module, the LED unit 30 in the LED module 10 with a built-in light-receiving element is sequentially lit. The brightness can be measured each time the LED is turned on. The LED control circuit compares the target brightness and the measured brightness, and corrects the lighting brightness so that it approaches the target. When the brightness is expressed by the drive voltage, the correction is performed to increase the drive voltage. When the brightness is expressed by repeating lighting and non-lighting, the ratio of the lighting time to the non-lighting time can be adjusted to make a correction.

[Embodiment 2]
Other embodiments of the present invention will be described below. For convenience of explanation, the same reference numerals are given to the members having the same functions as the members described in the above-described embodiment, and the description thereof will not be repeated.

[Backlight device configuration in which LED modules 10 with built-in light receiving elements are scattered]
FIG. 3 shows an aspect of the backlight 300 in which eight conventional LED modules 35 having no built-in light receiving element are arranged around the LED module 10 having a built-in light receiving element on one surface of the substrate. In the aspect of FIG. 3, the conventional LED module 35 is arranged so as to surround the LED module 10 with a built-in light receiving element, but the present invention is not limited to such a matrix form. Although the display of the resin 20 is omitted for the sake of brevity, in a preferred embodiment, each module is covered and packaged so as to be protected by the resin 20. A case where nine modules including the LED module 10 with a built-in light receiving element are arranged as one block (matrix arrangement of 3 × 3) to form a substrate is described (matrix arrangement of 2 blocks × 2 blocks). The brightness of the conventional LED module 35 without a built-in light receiving element in the periphery is measured by the light receiving element 40 in the LED module 10 with a built-in light receiving element in the center of the block.

The LED may be turned on sequentially for each module to measure the brightness, or the LED may be turned on for each block to measure the brightness. By measuring the brightness for each block, the correction for each area specified by the block becomes easy.

In FIG. 3, one block shows a matrix array of 3 × 3, but any numerical value can be adopted as the number of arrays. Further, although the matrix array of 2 blocks × 2 blocks is shown as a whole, any numerical value can be adopted as the number of arrays. In a preferred embodiment, the LED modules 10 with built-in light-receiving elements are arranged in a matrix so that at least the LED modules 10 with built-in light-receiving elements are adjacent to the conventional LED modules 35 without built-in light-receiving elements on one surface of the substrate. Can be. In this case, a block can be configured in which the distance between one LED module 10 with a built-in light-receiving element and another LED module 10 with a built-in light-receiving element at the shortest distance is one side length. Also in this case, the brightness of the conventional LED module 35 having no built-in peripheral light-receiving element can be measured by the light-receiving element 40 in the light-receiving element built-in LED module 10 at the center of the block. In a preferred embodiment, the LED control circuit (not shown) is arranged on a surface opposite to the surface of the substrate on which each module is arranged.

[Embodiment 3]
The transparent resin covering the LED deteriorates with time, and the transparency decreases. As shown in FIG. 1, the light receiving element 40 of the LED module 10 with a built-in light receiving element needs to be covered with a resin for protection, but when the resin deteriorates, there is a difference between the brightness on the substrate surface and the brightness measured by the light receiving element 40. Occurs. This also applies to the conventional light receiving element packaged as a single unit. However, although there is no means for correcting with the conventional light receiving element, it is possible to measure the degree of fogging of the resin by using the LED module 10 with a built-in light receiving element.

By measuring the brightness of one LED with a plurality of light receiving elements and comparing it with the data at the time of shipment, the transmittance of the resin is estimated and the brightness is corrected.

In the brightness correction method of the preferred embodiment, the measured value of the light receiving element (first light receiving element) built in the same module as the LED unit 30 for brightness reduction measurement and the light receiving element (first light receiving element) built in another module. 2) Compare with the measured value of the light receiving element). By such a comparison, it is possible to calculate the state of decrease in the brightness of the LED as seen from the outside of the package.

In FIG. 3, when the transparent resin of the LED module 10 with a built-in light-receiving element becomes cloudy, the brightness of the conventional LED module 35 without a built-in light-receiving element in the vicinity is measured low. By measuring the brightness of the LED module 10 with a built-in light receiving element in one place with a plurality of light receiving elements and comparing it with the data at the time of shipment, it is possible to estimate the degree of cloudiness of the resin and correct the measured value of the brightness. can. For example, the measurement result of the brightness by the light receiving element of one LED module A with a built-in light receiving element is measured as 70% of the brightness at the time of shipment from the factory, and the measurement result of the brightness by the light receiving element of another LED module B with a built-in light receiving element is the factory. It is assumed that the brightness is measured as 80% of the factory brightness. In this case, from the two measurement results, it is estimated that the light receiving sensitivity of the LED module with a built-in light receiving element of A is reduced to about 87.5% (= 70% ÷ 80%) due to the fogging of the resin 20. Correct the measured value. Repeating this with a module that covers the entire backlight will improve accuracy.

In another preferred embodiment, the reduced brightness of the LED module as seen from the outside of the package can be used for evaluation. Specifically, the light receiving measurement result by the light receiving element built in the light receiving element built-in LED module C for which the brightness reduction is to be evaluated and the light receiving measurement result of the light receiving element built in another light receiving element built-in LED module D are used. Then, the reduced state of the brightness of the LED module is evaluated.

When the LED portion 30 of the LED module C with a built-in light-receiving element has a brightness of 90% of the factory default, according to the light-receiving measurement result of the light-receiving element 40 (first light-receiving element) built in the LED module C with a built-in light-receiving element. Is assumed. However, if the light receiving measurement result (90%) of the light receiving element (first light receiving element) built in the light receiving element built-in LED module C is adopted as it is, the decrease in brightness is estimated to be low because the decrease in the transmittance of the resin is not taken into consideration. It will be too much. On the other hand, if the light receiving measurement result (for example, 81.225%) by the light receiving element built in the light receiving element built-in LED module D is used, the decrease in the transmittance of the resin of the package of the light receiving element built-in LED module D is also included. , The decrease in brightness will be overestimated. Hereinafter, the light receiving element built in the light receiving element built-in LED module C is referred to as "light receiving element C" (first light receiving element), and the light receiving element built in the light receiving element built-in LED module D is referred to as "light receiving element D" (second light receiving element D). (Light receiving element).

Since the LED module C with a built-in light receiving element and the LED module D with a built-in light receiving element use the same resin 20 in the same environment, it is assumed that the decrease in the transmittance of both resins 20 is the same. The difference between the light receiving measurement result (90%) of the light receiving element C (first light receiving element) and the light receiving measurement result (81.225%) of the light receiving element D (second light receiving element) is the yellow color of both transparent resins. It is considered that this is due to the decrease in transmittance due to the change. Specifically, it is considered that the value of the square of the reduced transmittance of both transparent resins leads to the difference in the measurement results of both. Therefore, the reduced transmittance of the transparent resin can be calculated by the following formula:
Transmittance of transparent resin (compared to the time of shipment) =
(Measured value of light receiving element C (ratio at the time of shipment) ÷ light receiving element D (ratio at the time of shipment)) ^ (1/2).
In the above example, it can be calculated as (81.225% ÷ 90%) ^ (1/2) = 95%. That is, the measurement result (81.225%) of the light receiving element D (second light receiving element) is based on the measurement result (90%) of the light receiving element C (first light receiving element), and the transmittance of both transparent resins is 95. It can be confirmed that the value is multiplied by the square of% (81.225% = 90% × 95% × 95%).

For the original decrease in the brightness of the backlight, it is necessary to consider both the decrease in the brightness of the LED unit 30 and the decrease in the transmittance of the resin. The reduced luminance (light receiving sensitivity) can be calculated by multiplying the reduced luminance of the LED unit 30 and the reduced transmittance of the resin. As in the above example, when the brightness is 90% due to the deterioration of the LED portion 30 of the LED module C with a built-in light receiving element and the transmittance reduced due to the deterioration of the transparent resin is 95%, the decrease in brightness is as follows. Is calculated as follows. Specifically, the brightness is (90% × 95% =) 85.5% of the factory default. The measured value can be corrected using the calculation result.

In the above-mentioned example of calculating the transmittance of the resin, not only the embodiment as shown in FIG. 2, but also the LED module 10 with a built-in light receiving element as shown in FIG. 3 and the conventional LED module 35 without a built-in light receiving element are arranged in a mixed manner. It can also be applied to a backlight device configured in the above manner. Further, it can also be applied to a backlight device of the embodiment as shown in FIG. 6, which will be described later.

[Embodiment 4]
In a preferred embodiment, the light receiving element 40 functions by applying a reverse bias voltage to the diode. On the other hand, each light emitting diode (light emitting element) of the LED unit 30 is configured to emit light by applying a forward bias voltage to the diode. Therefore, by changing the bias voltage applied to the anode and cathode of one diode 410 to change the bias direction, the diode 410 can be used as a light receiving element and also as a light emitting element (LED unit 30). Can be done. That is, by providing the switching circuit 400 capable of switching the bias direction, the common diode 410 can be used as the light emitting element and can also be used as the light receiving element without preparing the light emitting element and the light receiving element respectively.

[Embodiment 5]
In another preferred embodiment, the light receiving element 40 functions by equipotentializing the anode and cathode without biasing the diode in the opposite direction. For example, as shown in FIG. 5A, when an LED is used as a light emitting element, it is configured to emit light by applying a forward bias voltage to each diode. On the other hand, for example, the bias voltage applied to the anode and cathode of each of the R (red) and B (blue) diodes can be changed by an external circuit. Specifically, the bias voltage applied to the anode and the cathode of each diode is changed, and the bias voltage is adjusted so that the anode and the cathode have the same potential. Thereby, in the example shown in FIG. 5 (b), the R (red) and B (blue) diodes can be used as the light receiving element, and the G (green) diode can be made to function as the light emitting element.

[Configuration of shared LED module 50]
The shared LED module 50 is equivalent in appearance to the LED unit 30 composed of three types of diodes that emit light of the three primary colors of red (R), green (G), and blue (B). In a preferred embodiment, the backlight device for mounting the shared LED module 50 includes an external circuit in which at least one of these diodes can be used as a light receiving element.

In the example of the fourth embodiment, the LED unit 30 composed of a common diode 410 and the switching circuit 400 are provided. As one aspect of the light source module, the LED unit 30 composed of the common diode 410 and the switching circuit 400 may be assembled and configured in the same package. In a preferred embodiment, the common diode 410 constituting the LED section 30 is packaged as a light source module so as to be protected by a transparent resin. In another embodiment, the switching circuit 400 is mounted on the backlight device as an external circuit rather than in the same package. In this case, since the switching circuit 400 is not assembled in the same package, the shared LED module 50 is substantially equivalent to the LED unit 30.

Also in the example of the fifth embodiment, for example, a circuit in which the anode and the cathode have the same potential for the R (red) and B (blue) diodes can be mounted on the backlight device as an external circuit. Also in this case, since the external circuit is not assembled in the same package, the shared LED module 50 is substantially equivalent to the LED unit 30.

[Structure of external circuit]
FIG. 4 shows an example of the bias direction switching circuit 400 according to the fourth embodiment. Switches 420 and 430 are provided at the respective terminals of the diode 410 to be switched in the bias direction. The switches 420 and 430 each include a light emitting side terminal and a light receiving side terminal as switching terminals. When the switches 420 and 430 are switched to the light emitting side terminal side, the diode 410 is biased in the forward direction, and the diode 410 functions as a light emitting element (LED). When the switches 420 and 430 are switched to the light receiving side terminal side, the diode 410 is biased in the opposite direction, and the diode 410 functions as a light receiving element.

FIG. 5 shows an example of a circuit configuration according to the fifth embodiment. As an example, a case where the anode and the cathode of the R (red) and B (blue) diodes are adjusted to the same potential by an external circuit will be described. In a preferred embodiment, as shown in FIG. 5B, the anode voltage is set to 0V (GND) and the cathode voltage is also set to 0V. For example, by turning on the transistors of the R (red) and B (blue) LED drivers, the R (red) and B (blue) diodes can be shorted to 0V. By doing so, the anode and cathode can be changed to the same potential without biasing the diode in the opposite direction. Thereby, in the example shown in FIG. 5 (b), the R (red) and B (blue) diodes can be used as the light receiving element, and the G (green) diode can be made to function as the light emitting element.

[Backlight device in which the shared LED module 50 is arranged]
FIG. 6 is an aspect of the backlight device 500 having an external circuit on the back surface of the backlight as viewed from the front surface. For example, in the embodiment of the fourth embodiment, a backlight in which a plurality of shared LED modules 50 including the switching circuit 400 of FIG. 4 in an LED control circuit (not shown) on the back surface of the substrate are arranged in a matrix on the front surface side of the backlight. It is one aspect of the device 500. In the fifth embodiment, the LED control circuit (not shown) on the back surface of the substrate is provided with an external circuit for turning on the transistor of the LED driver shown in FIG. 5 (b). This is one aspect of the backlight device 500 in which the shared LED module 50 shown in FIG. 5B is arranged in a matrix on the surface side of the backlight. Although the display of the resin 20 is omitted for the sake of simplicity, in a preferred embodiment, each shared LED module 50 is packaged so as to be protected by a transparent resin. Although FIG. 6 shows a 6 × 6 matrix array, any numerical value can be adopted as the number of arrays.

When used as a normal backlight, all the diodes are used as LEDs, and when measuring the deterioration of the module, the desired diode is used as a light receiving element, so that the degree of deterioration of the module can be investigated. Since the diode of any module can be selected as the light receiving element, deterioration of the desired module can be flexibly investigated without arranging the light receiving element in a predetermined place in advance.

In the above-described second embodiment, the LED module 10 with a built-in light-receiving element is arranged in a matrix so that at least the LED module 10 with a built-in light-receiving element is adjacent to the conventional LED module 35 without a built-in light-receiving element on the surface side of the backlight substrate. The aspect of arranging is shown. In the present embodiment, the shared LED modules 50 can be arranged in a scattered manner instead of the LED module 10 with a built-in light receiving element in the second embodiment. All of the scattered light receiving element built-in LED modules 10 may be replaced with the shared LED module 50, or a part of the scattered light receiving element built-in LED modules 10 may be replaced.

In the first embodiment described above, one aspect of the backlight 200 in which the LED module 10 with a built-in light receiving element is arranged in a matrix on the surface side of the backlight substrate is shown. The backlight device 500 of the present embodiment can be considered as a mode in which all of the LED modules 10 with built-in light receiving elements of the first embodiment are replaced with the shared LED modules 50. In a preferred embodiment, a part of the LED module 10 with a built-in light receiving element of the first embodiment may be replaced with the shared LED module 50.

〔summary〕
The light source module (LED module 10 with a built-in light receiving element) according to the first aspect of the present invention includes a light emitting element (LED unit 30), a light receiving element (40), and a transparent resin (resin 20). The LED unit 30) and the light receiving element (40) are assembled in the same package, and the light emitting element (LED unit 30) and the light receiving element (40) are packaged so as to be protected by a transparent resin (resin 20). It is characterized by that.

According to the above configuration, it is possible to provide a light source module that individually adjusts the brightness in the backlight device.

In the light source module (shared LED module 50) according to the second aspect of the present invention, in the first aspect, the light emitting element (LED unit 30) and the light receiving element (40) are made of a common diode, and the common diode. The common diode is made to function as a light emitting element (LED unit 30) or a light receiving element (40) by changing the bias voltage applied to the anode and the cathode.

According to the above configuration, it is possible to provide a light source module in which a common diode can be used as a light emitting element and can also be used as a light receiving element without separately preparing a light emitting element and a light receiving element.

The backlight device (200, 500) according to the third aspect of the present invention includes a plurality of light source modules (LED module 10 with built-in light receiving element, shared LED module 50) according to the first or second aspect, and the plurality of light source modules (light receiving element). The built-in LED module 10 and the shared LED module 50) are arranged in a matrix on one surface of the backlight substrate.

According to the above configuration, it is not necessary to arrange the LED and the light receiving element individually, and it is possible to improve the efficiency of manufacturing the backlight substrate.

The backlight device (300) according to the fourth aspect of the present invention further includes a plurality of LED modules (35) packaged so as to be protected by a transparent resin (resin 20), and the light source module (LED module 10 with a built-in light receiving element) is provided. , The shared LED module 50) and the LED module (35) are arranged in a matrix on one surface of the backlight substrate, and at least the light source module (LED module 10 with built-in light receiving element, shared LED module 50) is the LED. It is characterized in that it is arranged so as to be adjacent to the module (35).

According to the above configuration, one light source module (LED module 10 with built-in light receiving element, shared LED module 50) and another LED module with built-in light receiving element (LED module 10 with built-in light receiving element, shared LED module 50) at the shortest distance. A block having a distance as the length of one side can be configured, and by measuring the brightness of each block, the correction for each area defined by the block becomes easy.

The backlight device (200, 300, 500) according to the fifth aspect of the present invention is the first light source module (LED module 10 with built-in light receiving element, shared LED module 50) in the backlight device according to the third or fourth aspect. Regarding the brightness of the light emitting element (LED unit 30, diode 410) assembled in the above, the light receiving measurement result in the first light receiving element (light receiving element 40, diode 410) assembled in the first light source module and the second light receiving element. The transparent resin (resin 20) is compared with the light receiving measurement results of the second light receiving element (light receiving element 40, diode 410) assembled in the light source module (LED module 10 with built-in light receiving element, shared LED module 50). It is characterized by calculating the transmission rate of the LED.

According to the above configuration, by measuring the brightness of one LED with a plurality of light receiving elements and comparing it with the data at the time of shipment, the transmittance of the resin can be estimated and the brightness can be corrected. ..

The method for correcting the brightness of the backlight device according to the sixth aspect of the present invention is the first light source module (LED module 10 with a built-in light receiving element) arranged in the backlight device (200, 300, 500) according to the third or fourth aspect. , Light receiving measurement of the brightness of the light emitting element (LED unit 30, diode 410) assembled in the shared LED module 50) in the first light receiving element (light receiving element 40, diode 410) assembled in the first light source module. By comparing the result with the light receiving measurement result in the second light receiving element (light receiving element 40, diode 410) assembled in the second light source module (LED module 10 with built-in light receiving element, shared LED module 50). It is characterized in that the permeability of the transparent resin (resin 20) is calculated.

According to the above configuration, by measuring the brightness of one LED with a plurality of light receiving elements and comparing it with the data at the time of shipment, the transmittance of the resin can be estimated and the brightness can be corrected. ..

The present invention is not limited to the above-described embodiments, and various modifications can be made within the scope of the claims, and the embodiments obtained by appropriately combining the technical means disclosed in the different embodiments. Is also included in the technical scope of the present invention. Further, by combining the technical means disclosed in each embodiment, new technical features can be formed.

In the above aspect 1, the light source module (shared LED module 50) according to the seventh aspect of the present invention comprises a diode (410) in which the light emitting element (LED unit 30) and the light receiving element (40) are common, and is a switch. (420, 430) is further provided, and the diode (410) is made to function as a light emitting element (LED unit 30) or a light receiving element (40) by switching the switch.

According to the above configuration, it is possible to provide a light source module in which a common diode can be used as a light emitting element and can also be used as a light receiving element without separately preparing a light emitting element and a light receiving element.

In the light source module (shared LED module 50) according to the eighth aspect of the present invention, in the first aspect, the diode (R of the shared LED module 50) in which the light emitting element (LED unit 30) and the light receiving element (40) are common. (Red) or B (blue) diode)
By applying a forward bias to the common diode, the common diode functions as a light emitting element (LED unit 30).
It is characterized in that the common diode functions as a light receiving element (40) by changing the bias voltage so that the bias voltage of the anode and the cathode of the common diode becomes equal.

According to the above configuration, it is possible to provide a light source module in which a common diode can be used as a light emitting element and can also be used as a light receiving element without separately preparing a light emitting element and a light receiving element.

10 LED module with built-in light receiving element 20 Resin 30 LED part 40 Light receiving element 35 LED module 50 Shared LED module 200, 300, 500 Backlight device 400 Switching circuit 410 Diode 420, 430 Switch

Claims (6)

Equipped with multiple light source modules
A backlight device in which a plurality of the light source modules are arranged in a matrix on one surface of a backlight substrate.
The light source module is
Light emitting element and
With the light receiving element
With transparent resin
Equipped with
The light emitting element and the light receiving element are assembled in the same package.
The light emitting element and the light receiving element are packaged so as to be protected by a transparent resin.
Regarding the brightness of the light emitting element assembled in the first light source module, the light receiving measurement result in the first light receiving element assembled in the first light source module and the second light source assembled in the second light source module. A backlight device characterized in that the transmittance of the transparent resin is calculated by comparing with a light receiving measurement result in a light receiving element. It has multiple light source modules and multiple LED modules.
A backlight device in which a plurality of the light source modules are arranged in a matrix on one surface of a backlight substrate.
The light source module is
Light emitting element and
With the light receiving element
With transparent resin
Equipped with
The light emitting element and the light receiving element are assembled in the same package.
The light emitting element and the light receiving element are packaged so as to be protected by a transparent resin.
The LED module is
It has a light emitting element packaged to protect it with a transparent resin and does not have a light receiving element.
The light source module and the LED module are arranged in a matrix on the same surface of the backlight substrate.
A backlight device characterized in that at least the light source module is arranged so as to be adjacent to the LED module. The light emitting element and the light receiving element are made of a common diode.
The first or second aspect of the present invention, wherein the common diode functions as a light emitting element or a light receiving element by changing the bias voltage applied to the anode and the cathode of the common diode. Backlight device. An LED module in which a light emitting element is packaged so as to be protected by a transparent resin, and further provided with a plurality of LED modules not provided with a light receiving element .
The light source module and the LED module are arranged in a matrix on the same surface of the backlight substrate.
The backlight device according to claim 1 , wherein at least the light source module is arranged so as to be adjacent to the LED module. Regarding the brightness of the light emitting element assembled in the first light source module, the light receiving measurement result in the first light receiving element assembled in the first light source module and the second light source assembled in the second light source module. The backlight device according to claim 2 , wherein the transmittance of the transparent resin is calculated by comparing the light receiving measurement result with the light receiving element. Regarding the luminance of the light emitting element assembled in the first light source module arranged in the backlight device according to claim 2 , the light receiving measurement result in the first light receiving element assembled in the first light source module and the light receiving measurement result. A method for correcting the brightness of a backlight device, which comprises calculating the transmittance of the transparent resin by comparing it with a light receiving measurement result in a second light receiving element assembled in the second light source module.

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