TW202336539A - Led module, light emitting device and liquid crystal panel manufacturing device including same - Google Patents

Abstract

The present invention provides an LED module capable of easily narrowing a voltage value range corresponding to a current value having a certain range output from an optical sensor. The LED module (10) consists of a substrate (12), a plurality of LED (14) provided on the substrate (12), an LED power supply circuit (16) formed on the substrate (12), an optical sensor (18) provided on the substrate (12), and a resistor connected in series with the optical sensor (18). In addition, the resistor is capable of adjusting its resistance value.

Description

LED module, light irradiation device, and liquid crystal panel manufacturing device equipped with the same

The present invention relates to an LED module and a light irradiation device used for exposure when bonding two substrates or manufacturing a semiconductor in manufacturing a liquid crystal panel, and a liquid crystal panel manufacturing apparatus provided with the same.

Conventionally, for example, one or several large-scale mercury lamps rated at 12 kW are used as light sources in exposure apparatuses for semiconductor manufacturing and the like. However, when the number of mercury lamps used in one exposure device is small, even if one mercury lamp becomes unlit, the light intensity will immediately become insufficient and the exposure device will have to be stopped. Therefore, an exposure device using a large mercury lamp There are problems with production continuity.

Therefore, for example, a multi-lamp type exposure apparatus has been developed for most exposure apparatuses used in the production of color filters for liquid crystal panels (for example, Patent Document 1).

Furthermore, currently, LEDs (light emitting diodes) are widely used as various light sources.

In addition, a light irradiation device using a plurality of LEDs is also used in the manufacture of liquid crystal panels to bond two translucent substrates by irradiating light to a photocurable sealant disposed between these substrates (for example, Patent document 2).

However, in order to maintain a stable exposure process, the illumination on the exposure surface is required to be uniform and constant for a long time. However, LEDs have the characteristic that if used for a long time, they will deteriorate and the amount of light emitted will gradually decrease.

In order to cope with such attenuation, when the amount of light emitted decreases, the amount of power supplied to the LED is increased to adjust the amount of light emitted to the same level as the initial amount.

Specifically, in order to know the amount of light emitted from the LED, for example, a light sensor is mounted on a substrate on which the LED is mounted, and the power supplied to each LED is adjusted based on the amount of current (or voltage value) output by the light sensor based on the amount of light received. amount (as an example of an LED module equipped with a light sensor, Patent Document 3).

existing technical documents

patent documents

Patent Document 1: Japanese Patent Application Publication No. 2020-43012

Patent Document 2: Japanese Patent Application Publication No. 2011-76033

Patent Document 3: Japanese Patent Application Publication No. 2012-89601

In view of this, our inventors devoted themselves to further research, and began to carry out research and development and improvement, hoping to solve the above problems with a better invention, and after continuous testing and modification, the present invention came out.

The problem to be solved by the invention

However, the characteristics of photosensors vary due to individual differences, and there is a problem that even if photosensors of the same model receive the same amount of light, the amount of current output by each photosensor varies.

For example, even if multiple photosensors (phototransistors) receive the same amount of light under the conditions of [collector-emitter voltage = 5V, light source wavelength = 560nm, irradiance = 0.01mW/cm ² ], There is also a deviation of 2.8μA to 7.1μA in the output current from each light sensor. Even when photosensors with close characteristics are grouped together, there is a deviation of 4.5 μA to 7.1 μA.

If there is such a deviation in the output current from the photosensor, for example, in an LED module equipped with a photosensor that tends to have a small output current, the amount of light emitted will be higher than expected, possibly causing an excessive light amount. On the contrary, in an LED module equipped with a photosensor that tends to have a large output current, the amount of light emitted is lower than the expected amount of light emitted, which may lead to a state of insufficient light amount.

For example, when a photosensor with an output current of 4.5 μA is used and the voltage across a resistor connected in series with the photosensor becomes 1V when the illumination reaches an illumination equivalent to 100 mW, even if the illumination is the same as that of 100 mW, the For a resistor with a resistance value, in a photosensor with an output current of 7.1μA, the voltage across the resistor is also about 1.6V, and as a device, it is mistakenly recognized as an illumination equivalent to 160mW.

If misrecognition occurs in this way, the LED module is adjusted to reduce the amount of power supplied to the LED so that the voltage across both ends becomes 1V. As a result, the actual illumination is reduced to about 62.5mW (100mW/1.6), which is insufficient light.

Furthermore, since one light irradiation device includes a plurality of LED modules, if the amount of light emitted from each LED module varies as described above, the uniformity of the illumination on the irradiation surface of the light emitted from the entire light irradiation device will also vary. create problems.

The present invention was made in view of the above problems, and an object thereof is to provide an LED module that can easily narrow the width of the voltage value corresponding to the current value even when the current value output from the photosensor has a width. A light irradiation device and a liquid crystal panel manufacturing device equipped with the same.

Technical solutions to solve problems

According to one aspect of the present invention, an LED module is provided. The LED module is provided with:

substrate;

A plurality of LEDs arranged on the substrate;

An LED power supply circuit formed on the substrate;

a light sensor disposed on the substrate; and

With respect to the resistor connected in series with the light sensor,

The resistor can adjust the resistance value.

Preferably,

The resistor has:

fixed resistor;

a plurality of slave resistors connected in parallel with respect to the fixed resistor; and

A plurality of switching units are connected in series with respect to each of the slave resistors.

Preferably,

The LED module further includes an operational amplifier connected in parallel to the resistor and measuring the voltage across the resistor.

According to other aspects of the invention,

A light irradiation device is provided. The light irradiation device includes a plurality of the above-mentioned LED modules.

According to other aspects of the invention,

A liquid crystal panel manufacturing apparatus provided with the above-mentioned light irradiation device is provided.

Invention effect

According to the LED module, light irradiation device, and liquid crystal panel manufacturing device according to the present invention, since the resistor whose resistance value can be adjusted is connected in series with the photosensor, the resistance value is adjusted based on the output current from the photosensor, so that the output current In a state where a relatively large width exists, the width of the voltage value corresponding to the current value can be made relatively small.

Regarding the technical means of our inventors, several preferred embodiments are described in detail below along with the drawings, so that everyone can have a thorough understanding and recognition of the present invention.

(Structure of exposure device 100)

Hereinafter, the exposure device 100 including the light irradiation device 200 according to the embodiment to which the present invention is applied will be described. As shown in FIG. 1 , the exposure apparatus 100 mainly used when manufacturing liquid crystal panels and the like generally includes a light irradiation device 200 , an optical system component 102 , a workpiece mounting table 104 , and a workpiece transport device 106 .

The light irradiation device 200 is a device for radiating light L in order to expose a workpiece X such as a liquid crystal panel, and is configured by arranging a plurality of LED modules 10 on the same plane.

As shown in FIG. 2 , each LED module 10 roughly includes a substrate 12 , LED 14 , an LED power supply circuit 16 , a photosensor 18 , a photosensor circuit 20 , an output regulator 22 , a photosensor connector 24 , and a cover 26 .

The substrate 12 is a component on which the LED 14, the photosensor 18, etc. are mounted. The outer shape of the substrate 12 is not particularly limited, and may be a rectangular shape like this embodiment, or may be a square shape, or the like.

The LED 14 is an element that emits light of a predetermined wavelength by receiving electric power through the LED power supply circuit 16 . In the LED module 10 according to this embodiment, 20 LEDs 14 are mounted and arranged in a checkerboard pattern on the substrate 12 . In addition, the number of LEDs 14 arranged in one LED module 10 is not particularly limited, and the arrangement shape of the LEDs 14 is not particularly limited either.

As described above, the LED power supply circuit 16 has a function of supplying power for lighting to the LED 14 and is formed on the surface of the substrate 12 . Furthermore, in FIG. 2 , a portion of the LED power supply circuit 16 is depicted, and the remaining LED power supply circuit 16 is omitted.

The photosensor 18 is an element that receives light from the LED 14 in order to detect the amount of light emitted from the LED 14 and outputs an amount of current corresponding to the amount of light received. In the present embodiment, a “phototransistor” as the photosensor 18 is arranged on the substrate 12 so as to receive light from the LED 14 mounted at the center of the substrate 12 and at the lower part in the figure. In addition, as the photosensor 18, a "photodiode" may be used.

Specifically, as shown in FIG. 3 , the collector side of the photosensor 18 (phototransistor) is connected to the power supply line, and the emitter side is connected to the output adjustment unit 22 .

Returning to FIG. 2 , the photosensor circuit 20 has a function of electrically connecting the photosensor 18 , the output adjuster 22 and the photosensor connector 24 , and is formed on the surface of the substrate 12 .

The output adjuster 22 has a function of reducing the width of the amount of light emitted from each LED module 10 due to variation in the amount of output current due to individual differences in the photosensor 18. In the present embodiment, as shown in FIG. 3 As shown, there is a fixed resistor 30 connected in series with the emitter side of the light sensor 18 (phototransistor), a first slave resistor 32 and a second slave resistor 34 connected in parallel with the fixed resistor 30 . In addition, the resistance value of the first slave resistor 32 is set to be larger than the resistance value of the second slave resistor 34 . In addition, the number of these slave resistors 32 and 34 is not particularly limited, as long as it is two or more.

In addition, the first switching unit 36 and the second switching unit 38 are connected in series to the first slave resistor 32 and the second slave resistor 34 respectively. Accordingly, by opening and closing the first switching unit 36 and the second switching unit 38 respectively, the overall resistance value of the fixed resistor 30 , the first slave resistor 32 and the second slave resistor 34 connected in parallel can be adjusted.

In this embodiment, jumper wires are used as the first switching unit 36 and the second switching unit 38 for opening/shorting. However, as the jumper wires, metal wires, etc. may be used, or solder on the substrate may be used. In addition, it is not limited to a jumper wire, and a switch can also be used in a dip switch etc.

In addition, the output adjustment unit 22 according to this embodiment further includes: a first capacitor 40 connected in series with the photosensor 18; and a second capacitor 42 connected with the photosensor 18, the fixed resistor 30, the first slave resistor 32, The second slave resistor 34 and the first capacitor 40 are connected in parallel.

The photosensor connector 24 is a terminal connected to a voltmeter (not shown) for measuring the voltage across the fixed resistor 30 , the first slave resistor 32 , and the second slave resistor 34 connected in parallel. In this embodiment, in addition to the above-mentioned two terminals (the No. 2 terminal [sensor output terminal] and the No. 3 terminal [ground terminal] in the figure), a No. 1 terminal [3V] connected to the collector side of the photosensor 18 is provided. terminal], but the No. 1 terminal is not a necessary component.

Returning to FIG. 2 , the cover 26 is a member for guiding light from the LED 14 to the light sensor 18 , and is attached to the surface of the substrate 12 so as to cover the light sensor 18 and one LED 14 located near the light sensor 18 .

As shown in FIG. 4 , the cover 26 according to this embodiment has a cover body 50 , an LED storage space 52 , a photosensor storage space 53 , a light guide slit 54 and a boss 56 .

The cover main body 50 is a substantially rectangular thick plate-shaped member made of resin such as polycarbonate.

A through hole serving as the LED housing space 52 is formed on the surface of the cover body 50 (the surface facing outward when mounted on the substrate 12 ). The LED receiving space 52 has a substantially circular cross-section, and its diameter gradually increases toward the surface.

Formed on the back surface of the cover body 50 (the surface facing the substrate 12 when mounted on the substrate 12 ) are: a through hole that serves as the above-mentioned LED storage space 52 ; a recess that serves as the photosensor storage space 53 ; and a through hole that connects the LED storage space 52 and the light sensor. The sensor receiving space 53 communicates with the light guide slit 54 of the groove. In the present embodiment, the cross-section of the photosensor housing space 53 is formed in a substantially rectangular shape, but the cross-sectional shape of the photosensor housing space 53 is not particularly limited.

Furthermore, a pair of bosses 56 are provided protruding from the back surface of the cover body 50 . In this embodiment, each boss 56 is formed in a cylindrical shape, but it may also be in a prism shape or the like.

A boss insertion hole 58 into which a pair of bosses 56 on the cover 26 is inserted is formed at a predetermined position on the base plate 12. When the boss 56 is inserted into the boss insertion hole 58 and the cover 26 is installed on the base plate 12, The light sensor 18 is housed in the light sensor receiving space 53 , and the LED holding space 52 houses one LED 14 .

Furthermore, only the light emitted from the accommodated LED 14 passes through the light guide slit 54 and is received by the photosensor 18 , and the amount of light received by the photosensor 18 is not affected by the light from other LEDs 14 .

In addition, in this embodiment, as shown in FIG. 5 , the boss insertion hole 58 is formed such that the diameter of the back surface of the substrate 12 is larger than the diameter of the front surface, and the front end portion of the boss 56 inserted into the boss insertion hole 58 passes therethrough. The boss 56 is melted by a soldering iron or the like heated (for example, 200° C.) so that the front end does not protrude from the back side of the substrate 12 , and is filled in the boss insertion hole 58 on the back side of the substrate 12 (thermal caulking). This prevents the cover 26 from accidentally detaching from the substrate 12 .

Returning to FIG. 1 , the optical system component 102 has the function of guiding the light L emitted from the light irradiation device 200 to the irradiation surface on the workpiece mounting table 104 , and roughly includes a fly-eye lens 108 , a shutter 110 , a parallelizing mirror 112 and a reflecting mirror 114 .

The fly's eye lens 108 is a component for receiving the light L from the light irradiation device 200 and uniformizing the light L irradiated onto the irradiation surface on the workpiece mounting table 104 via the parallelizing mirror 112 and the like. The fly's eye lens 108 is configured by combining a plurality of lenses 109 .

The shutter 110 is a device having a function of allowing or blocking the light L emitted from the fly-eye lens 108 to control the exposure time of the workpiece X and the like.

The collimator mirror 112 is a component that has the function of making the light L that has passed through the shutter 110 become parallel light.

The reflecting mirror 114 is a member that reflects the light L converted into parallel light by the collimating mirror 112 toward the irradiation surface on the workpiece mounting table 104 .

In addition, the structure of the optical system component 102 according to this embodiment is just an example, and the number of components constituting the optical system component 102 and their arrangement positions/arrangements are determined according to various conditions such as the overall layout of the exposure apparatus 100 order. For example, a method in which the shutter 110 is not used in the optical system component 102 may be considered.

The workpiece mounting table 104 is a table on which the workpiece X exposed by the light L is placed.

The workpiece conveying device 106 is a device that moves the workpiece mounting table 104 and the workpiece X in a predetermined direction/distance, and uses a known actuator or the like.

(Adjustment of light sensor 18 in LED module 10)

Next, in a state where the current value output from each photosensor 18 in each LED module 10 has a relatively large width, an adjustment procedure for making the width of the voltage value output based on the current value relatively small will be described.

For example, as shown in FIG. 6 , it is assumed that the current value output from each photosensor 18 in each LED module 10 has a width of 3 μA to 7 μA. At this time, if only the fixed resistor 30 is provided in the output adjustment unit 22 , the voltage across the fixed resistor 30 detected based on the current value will be in the range of 0.6V to 1.6V.

Therefore, when the first slave resistor 32 of the output adjustment unit 22 is connected in parallel with the fixed resistor 30 (that is, the first switching unit 36 is closed (short-circuited)), and the second slave resistor 34 is disconnected (that is, the first slave resistor 32 is connected in parallel with the fixed resistor 30 ), , with the second switching unit 38 turned off (open circuit), the voltage across the fixed resistor 30 (that is, the voltage between the No. 2 terminal and the No. 3 terminal in the photosensor connector 24 ) is measured. If the measured voltage value falls within a given range (for example, from 0.8V to 1.2V as shown in Figure 7), no adjustment is required.

If the measured voltage value is slightly higher than the given range (area A in the figure), the second slave resistor 34 is connected in parallel with the fixed resistor 30 (that is, the second switching unit 38 is set to closed ( short circuit)), causing the first slave resistor 32 to be disconnected with respect to the fixed resistor 30 (that is, disconnecting the first switching unit 36 (open circuit)). Therefore, since the measured voltage is within the given range, the voltage value is measured again and confirmed.

In addition, when the measured voltage value is significantly higher than the predetermined range (region B in the figure), the first slave resistor 32 is kept connected to the fixed resistor 30, and the second slave resistor 34 is connected to the fixed resistor 30. The resistor 30 is connected in parallel (that is, the second switching unit 38 is closed (short-circuited)). Therefore, since the measured voltage is within the given range, the voltage value is measured again and confirmed.

Furthermore, when the measured voltage value is lower than a given range (region C in the figure), the second slave resistor 34 remains unconnected, causing the first slave resistor 32 to be disconnected with respect to the fixed resistor 30 ( That is, the first switching unit 36 is turned off (open circuit)). Therefore, since the measured voltage is within the given range, the voltage value is measured again and confirmed.

As described above, according to the LED module 10 according to the embodiment, a resistor whose resistance value can be adjusted is connected in series with the photosensor 18. Therefore, by adjusting the resistance value based on the output current from the photosensor 18, there is a relatively large width in the output current. In this state, the width of the voltage value corresponding to the current value can be made relatively small.

(Modification 1)

In the above-described embodiment, the fixed resistor 30 and the plurality of slave resistors 32 and 34 are used as the resistance of the output adjustment unit 22. However, in addition, a thermistor (the resistance changes with temperature change) may also be used. larger resistor body). The thermistor has the characteristic that its resistance value decreases when its temperature becomes high, and its resistance value increases when its temperature becomes low. By connecting the thermistor in parallel with the fixed resistor 30 and the like, when the amount of light received by the photosensor 18 does not change due to the temperature change of the photosensor 18, but the output current value from the photosensor 18 fluctuates, the current can be adjusted to the same value. The width of the change in the value corresponds to a smaller width of the voltage value.

(Modification 2)

In addition, in the output adjustment unit 22 of the above-described embodiment, the resistance value is adjusted by connecting/unconnecting the plurality of slave resistors 32 and 34. However, instead of these slave resistors 32 and 34, as shown in FIG. 8, a volumetric device may be used. Resistor (variable resistor) 44.

(Modification 3)

Furthermore, in the output adjuster 22 of the above-described embodiment, the output current value from the photosensor 18 is converted into a voltage value by measuring the voltage across the resistor. However, an operational amplifier may be used instead to convert the current value into a voltage value. Value conversion.

For example, as shown in Figure 9, connect the inverting input of operational amplifier 300 to the cathode side of photosensor 302 (photodiode), and connect the non-inverting input to ground. Furthermore, the fixed resistor 30 and the plurality of slave resistors 32 and 34 are connected in parallel with respect to the operational amplifier 300 , that is, between the inverting input and the output of the operational amplifier 300 .

In the case of this modification 3, the photosensor connector 24 has a No. 1 terminal [ground terminal] and a No. 2 terminal [sensor output terminal], and the voltage between these terminals is measured.

Like the above-described embodiment, even when the operational amplifier 300 is used, the first switching unit 36 and the second switching unit 38 connected in series to the plurality of slave resistors 32 and 34 are opened and closed to adjust the resistance value.

(Modification 4)

In the above-described embodiment, an example is described in which the LED module 10 and the light irradiation device 200 according to the present invention are applied to the exposure device 100. However, these LED modules 10 and the light irradiation device 200 may also be applied to a liquid crystal panel manufacturing apparatus.

It should be understood that the embodiments disclosed this time are illustrative and not restrictive in every respect. The scope of the present invention is shown not by the above description but by the claims, and includes all changes within the meaning and range equivalent to the scope of the claims.

In summary, the technical means disclosed in the present invention can indeed effectively solve the problems of conventional knowledge and achieve the expected purposes and effects. They have not been published in publications or publicly used before the application and are of long-term progress. They are truly worthy of the title. The invention described in the Patent Law is correct, and I submit the application in accordance with the law. I sincerely pray that Jun will review it carefully and grant an invention patent. I am deeply grateful.

However, the above are only several preferred embodiments of the present invention, and should not be used to limit the scope of the present invention. That is, all equivalent changes and modifications made based on the patent scope of the present invention and the content of the invention specification are It should still fall within the scope of the patent of this invention.

[Invention] 10:LED module 100:Exposure device 102: Optical system components 104: Workpiece mounting table 106: Workpiece conveying device 108:Fly's Eye Lens 109:Lens 110:Shutter 112:Parallelizing mirror 114:Reflector 12:Substrate 14:LED 16:LED power supply device 18:Light sensor 20:Light sensor circuit 200:Light irradiation device 22:Output adjustment section 24: Connector for light sensor 26:hood 30: Fixed resistance 300: Operational amplifier 302:Light sensor 32: First slave resistor 34: Second slave resistor 36: First opening and closing unit 38: Second opening and closing unit 40:First capacitor 42: Second capacitor 44:Volume resistance 50: cover body 52:LED storage space 53: Light sensor storage space 54:Light guide slit 56:Boss 58: Boss embedded hole X: workpiece L:Light

[Fig. 1] is a diagram showing an exposure device 100 according to an embodiment to which the present invention is applied; [Fig. 2] is a diagram showing an LED module 10 according to an embodiment to which the present invention is applied; [Fig. 3] is a circuit diagram of the output adjustment unit 22 according to the embodiment; [Fig. 4] A diagram showing the cover 26 according to the embodiment, in which (a) is a front view, (b) is a rear view, and (c) is an X-X cross-sectional view; [Fig. 5] is a cross-sectional view showing a state in which the cover 26 is attached to the substrate 12; [Fig. 6] is a graph showing the current value output from the photosensor 18 and the voltage across the resistor detected based on the current value; [Fig. 7] is a graph showing the current value output from the photosensor 18 and the voltage across the resistor detected based on the current value; [Fig. 8] is a circuit diagram of the output adjustment unit 22 according to Modification 2; [Fig. 9] is a circuit diagram of the output adjustment unit 22 according to Modification 3.

10:LED module

12:Substrate

14:LED

16:LED power supply device

18:Light sensor

20:Light sensor circuit

22:Output adjustment section

24: Connector for light sensor

26:hood

Claims (5)

An LED module having: substrate; A plurality of LEDs arranged on the substrate; LED power supply circuit formed on the substrate; a light sensor arranged on the substrate; and resistor, connected in series with respect to the light sensor, The resistor can adjust the resistance value. The LED module as described in claim 1, wherein, The resistor has: fixed resistor; a plurality of slave resistors connected in parallel with respect to the fixed resistor; and A plurality of switching units are connected in series with respect to each of the slave resistors. The LED module as described in claim 1, wherein, The LED module further includes an operational amplifier connected in parallel with the resistor and measuring the voltage across the resistor. A light irradiation device, wherein, The light irradiation device includes a plurality of LED modules as described in any one of claims 1 to 3. A liquid crystal panel manufacturing device, wherein, The liquid crystal panel manufacturing apparatus includes the light irradiation device according to claim 4.

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