TWI802626B - Ultraviolet curing apparatus - Google Patents

Abstract

An ultraviolet curing apparatus includes an LED module including a circuit board and a plurality of light emitting diodes (LEDs), a cover glass disposed in front of the LED module, an illuminance sensor installed on the circuit board, and a light shielding portion provided to face the illuminance sensor in front of the cover glass. The illuminance sensor measures the illuminance of ultraviolet rays reflected from the cover glass among ultraviolet rays emitted from the plurality of LEDs. The light shielding portion blocks the inflow of external light directed to the illuminance sensor.

Description

UV Curing Unit

The present invention relates to UV curing devices, and more particularly to UV curing devices capable of easily measuring and controlling light emitting diode (LED) illumination.

Ultraviolet curing is a technique of curing a liquid material into a solid using ultraviolet rays, and is widely used in the manufacture of various electronic devices and displays such as organic light emitting display (OLED) and liquid crystal display (LCD) devices. device. Among ultraviolet curing devices, ultraviolet LED curing devices using light-emitting diodes (LEDs) have advantages such as low power consumption, long life, and easy selection of light-emitting wavelength bands.

The ultraviolet curing device can be used to cure the resin in the manufacturing process of the display device. For example, the process of attaching a display panel and a touch screen panel includes: a first step of applying resin to the entire surface of the display panel; a second step of temporarily curing the resin by irradiating ultraviolet light to the edge of the display panel; a third step , configuring the touch screen panel on the display panel; and the fourth step, completely curing the entire resin.

Ultraviolet rays emitted from a plurality of LEDs provided in the ultraviolet curing device are irradiated to the resin through the cover glass. For a real curing process, it is necessary to measure the illuminance (light quantity) of ultraviolet light incident on the resin and control the driving current of the LED based on the measurement result.

The object of the present invention is to provide an ultraviolet curing device capable of calculating the illuminance of ultraviolet rays incident on an object in real time and controlling the driving current of a light emitting diode (LED) to accurately achieve the intended illuminance.

The ultraviolet curing device according to the present invention includes: a light emitting diode (LED) module, which includes a circuit board and a plurality of light emitting diodes; a cover glass, which is arranged in front of the LED module; an illuminance sensor, which is installed on on the circuit board to measure the illuminance of ultraviolet rays reflected from the cover glass among the ultraviolet rays emitted from the plurality of light emitting diodes; and a light shielding part provided to face the illuminance sensor in front of the cover glass, and to shield the directional illuminance External light to the sensor.

A plurality of light emitting diodes may be arranged in a line along a longitudinal direction of the circuit board. The illuminance sensor can be disposed on the edge of the circuit board and be separated from the plurality of light emitting diodes along the width direction of the circuit board by a distance.

Multiple LED modules can be set. A plurality of LED modules can be arranged in a straight line along the longitudinal direction of the circuit board. Each LED module can be provided with at least one illuminance sensor.

The ultraviolet curing device may further include a housing to support the LED module and the cover glass. The light shielding part may include: a supporting part parallel to the housing; and a shielding part connected to the supporting part and overlapping the illuminance sensor with a distance from the cover glass.

The light shielding part may include stainless steel. The shield part may be formed to be bent at a right angle with respect to the support part.

The ultraviolet curing device may further include a control unit electrically connected to the LED module and the illuminance sensor. The control unit can adjust the current supplied to the LED module based on the illuminance of reflected ultraviolet rays measured by the illuminance sensor.

When the illuminance of reflected ultraviolet rays measured by the illuminance sensor is lower than a predetermined reference illuminance, the control unit may increase the amount of current supplied to the LED module. When the illuminance of reflected ultraviolet rays measured by the illuminance sensor is higher than the reference illuminance, the control unit may reduce the amount of current supplied to the LED module. ＜Invention effects＞

The UV curing unit prevents the inflow of external light toward the illuminance sensor, and correctly calculates the illuminance of transmitted ultraviolet rays. The current of a light emitting diode (LED) can be precisely controlled based on the calculated illuminance. Therefore, the UV curing device can correctly realize the intended illuminance in a real UV curing process, and can improve the quality of cured products.

The present disclosure will be described more fully hereinafter with reference to the accompanying drawings, which show exemplary embodiments of the disclosure. As those skilled in the art will realize, the specific aspects described may be modified in various different ways, all without departing from the spirit and scope of the present disclosure.

1 and 2 are perspective views of an ultraviolet curing device according to an embodiment of the present invention, and FIG. 3 is a cross-sectional view of the ultraviolet curing device shown in FIG. 1 . FIG. 2 shows the state that the ultraviolet (UV) curing device of FIG. 1 is turned upside down.

1 to 3, the ultraviolet curing device 100 includes: a light emitting diode (LED) module 10, which includes a circuit board 11 and a plurality of LEDs 12; a cover glass 20, which is positioned in front of the LED module 10; a housing 30 , which supports the LED module 10 and the cover glass 20; the illuminance sensor 40, which is disposed on the circuit board 11;

The plurality of LEDs 12 may be of a chip on board type mounted on the circuit board 11 . LED is a light source used in various fields depending on the wavelength. The plurality of LEDs 12 may emit ultraviolet light having a wavelength of about 315 nm to 400 nm and an output of several watts (W) to several tens of watts in the ultraviolet curing device 100 .

The plurality of LEDs 12 may be arranged in a line along the longitudinal direction (x direction) of the circuit board 11 with gaps therebetween. A plurality of LEDs 12 aligned in the x direction may be arranged in at least two columns along the width direction (y direction) of the circuit board 11 .

The ultraviolet curing device 100 may include a plurality of LED modules 10 . A plurality of LED modules 10 can be arranged in a straight line along the longitudinal direction (x direction) of the circuit board 11 . In this case, the ultraviolet curing device 100 is a bar type device and may emit linear ultraviolet beams. Although the ultraviolet curing device 100 shown in FIG. 2 combines four LED modules 10, the number of LED modules 10 is not limited to the illustrated example.

The LED module 10 generates heat during operation, so the functionality of the plurality of LEDs 12 can be compromised. The UV curing device 100 may therefore include a cooling unit 60 behind the LED module 10 .

The cooling unit 60 may be constructed as a water-cooled type (in which cooling water is circulated) or an air-cooled type (in which cooling air is circulated). The function of the cooling unit 60 is to cool the heat generated by the LED module 10 during the operation of the ultraviolet curing device 100 to stabilize the operation of the plurality of LEDs 12 .

The cover glass 20 is disposed in front of the LED module 10 , and the housing 30 supports the LED module 10 and the cover glass 20 . The housing 30 is positioned on four sides of the LED module 10 to surround the plurality of LEDs 12 , and the formed height is greater than the thickness of the LED module 10 . The edge of the cover glass 20 can be fitted into the housing 30 and fixed to the housing 30 .

Most of the ultraviolet rays emitted from the plurality of LEDs 12 pass through the cover glass 20 to reach the object to be irradiated, and the rest are reflected from the cover glass 20 . The ultraviolet rays transmitted through the cover glass 20 are called “transmitted ultraviolet rays” L1, and the ultraviolet rays reflected from the cover glass 20 are called “reflected ultraviolet rays” L2. The illuminance sensor 40 is mounted on the circuit board 11 and detects the illuminance of the reflected ultraviolet L2.

Each LED module 10 can be provided with at least one illuminance sensor 40 , and the illuminance sensor 40 can be directly installed on the circuit board 11 . The illuminance sensor 40 may be positioned at the edge of the circuit board 11 a distance away from the plurality of LEDs 12 along the width direction (y direction) of the circuit board 11 . In this case, the illuminance sensor 40 may be installed parallel to the plurality of LEDs 12 without affecting the arrangement of the plurality of LEDs 12 . The location of the illuminance sensor 40 is not limited to the above examples.

The illuminance sensor 40 may be composed of a photodiode to convert light energy into electrical energy. When light reaches the photodiode there is a current, and the magnitude of the voltage across the photodiode can be almost proportional to the intensity of the light. The ratio of the transmitted ultraviolet rays L1 to the reflected ultraviolet rays L2 is determined according to the transmittance of the cover glass 20 . The illuminance sensor 40 can calculate the illuminance of the transmitted ultraviolet L1 according to the sensed illuminance of the reflected ultraviolet L2.

For this purpose, before the actual curing process, the illuminance of transmitted ultraviolet L1 and reflected ultraviolet L2 may be experimentally changed, and the experimental results may be stored in a memory (not shown) of the ultraviolet curing device 100 . The calculation of the illuminance of the transmitted ultraviolet L1 may be to read the illuminance of the transmitted ultraviolet L1 that matches the illuminance value of the reflected ultraviolet L2 sensed by the illumination sensor 40 during the actual curing process.

The control unit 70 can control the current supplied to the LED module 10 based on the illuminance of the reflected ultraviolet L2 sensed by the illuminance sensor 40 . Therefore, the control unit 70 can control the illuminance of the ultraviolet rays emitted from the LED module 10 . For example, the control unit 70 can control the LED module 10 so that the illuminance of the transmitted ultraviolet L1 becomes the reference illuminance of the transmitted ultraviolet.

The reference transmitted ultraviolet irradiance refers to the optimal transmitted ultraviolet intensity, which is preset according to the characteristics of the object to be irradiated (for example, a UV-curable resin). The reference transmitted ultraviolet illuminance can be variously set according to the composition of the resin, the thickness of the resin, the distance between the resin and the LED module 10, and the like. The illuminance matching the reference transmitted ultraviolet illuminance among the reflected ultraviolet L2 illuminance measured by the illuminance sensor 40 is called "reference illuminance".

In a real curing process, when the illuminance of the reflected ultraviolet L2 measured by the illuminance sensor 40 is lower than the reference illuminance, the control unit 70 increases the current supplied to the LED module 10 to increase the illuminance of the transmitted ultraviolet L1. Relatively speaking, when the illuminance of the reflected ultraviolet L2 measured by the illuminance sensor 40 is higher than the reference illuminance, the control unit 70 reduces the current supplied to the LED module 10 to reduce the illuminance of the transmitted ultraviolet L1.

In this way, the control unit 70 adjusts the current supplied to the LED module 10 in real time according to the illuminance of the reflected ultraviolet L2 measured by the illuminance sensor 40 . Therefore, the illuminance of the transmitted ultraviolet rays (L1) reaching the object to be irradiated can match the illuminance of the reference transmitted ultraviolet rays.

The transmittance of the cover glass 20 may be in the range of approximately 90% to 95%. If the transmittance of the cover glass 20 is less than 90%, the illuminance of the transmitted ultraviolet L1 becomes low, and the object may not be properly cured. When the transmittance of the cover glass 20 exceeds 95%, the illuminance of the reflected ultraviolet L2 incident on the illuminance sensor 40 is reduced, and an error in calculating the illuminance of the transmitted ultraviolet L1 may increase.

Not only the reflected ultraviolet rays L2, but also the ultraviolet rays introduced from the outside (outside of the cover glass 20 ) can also reach the illuminance sensor 40 of the above-mentioned ultraviolet curing device 100 . For example, when the display panel and the touch screen panel are combined using resin, part of the transmitted ultraviolet light L1 may be reflected from the surface of the touch screen panel and directed to the ultraviolet curing device 100 .

In this case, since the amount of ultraviolet rays greater than the amount of reflected ultraviolet rays L2 is incident on the illuminance sensor 40 , when the control unit 70 calculates the illuminance of transmitted ultraviolet rays L1 , the illuminance higher than the real illuminance can be calculated. Then, even if the illuminance of the transmitted ultraviolet L1 does not reach the reference transmitted ultraviolet illuminance, the control unit 70 determines that the illuminance of the transmitted ultraviolet L1 is normal and the ultraviolet curing device 100 cannot correctly achieve the intended light intensity.

In the ultraviolet curing device 100 of this embodiment, the light shielding part 50 is disposed so as to face the illumination sensor 40 in front of the cover glass 20 , and block external light from flowing toward the illumination sensor 40 . The light shielding portion 50 can be made of a material that blocks ultraviolet rays, such as stainless steel, and can be fixed to the housing 30 .

The light shielding part 50 may include a supporting part 51 and a blocking part 52 . The supporting part 51 is fixed to the housing 30 , and the blocking part 52 is connected to the supporting part 51 to face the illuminance sensor 40 along the ultraviolet emission direction (-z direction in the drawing).

The supporting part 51 may be parallel to the housing 30 , and the blocking part 52 may be constructed to be bent at a right angle with respect to the supporting part 51 . The blocking part 52 may be spaced apart from the cover glass 20 by taking a predetermined distance. The structure of the light shielding part 50 is not limited to the above examples, and can be applied to any structure as long as it can block external light from entering the illuminance sensor 40 .

Since the light shielding part 50 is positioned to face the illuminance sensor 40 on the outside of the cover glass 20, the ultraviolet curing device 100 can shield the ultraviolet rays introduced from the outside (for example, the surface of the touch screen panel can be effectively avoided The ultraviolet rays reflected and directed to the LED module 10 enter the illuminance sensor 40).

Therefore, the reflected ultraviolet L2 excluding external light is incident on the illuminance sensor 40 , and the control unit 70 can correctly calculate the illuminance of the transmitted ultraviolet L1 from the illuminance of the reflected ultraviolet L2 measured by the illuminance sensor 40 . As a result, the ultraviolet curing device 100 can correctly achieve the intended light intensity, and the curing quality of the resin can be improved.

FIG. 4 is a schematic perspective view showing a temporary curing step of resin using the ultraviolet curing device shown in FIG. 1 .

Referring to FIGS. 3 and 4 , an example of a curing process according to an aspect may be the process of attaching the display panel 201 and the touch screen panel 202 together. The process of attaching the display panel 201 and the touch screen panel 202 includes: a first step of applying resin 203 to the entire surface of the display panel 201; a second step of irradiating ultraviolet light to the edge of the display panel 201 to temporarily cure the edge of the resin 203 ; The third step is to configure the touch screen panel 202 on the display panel 201 ; and the fourth step is to completely cure the entire resin 203 .

In the second step, four ultraviolet curing devices 100 can be aligned and arranged on four edges of the display panel 201 . Linear ultraviolet beams are irradiated from the four ultraviolet curing devices 100 to the edge of the display panel 201, and the resin 203 is temporarily cured to form a bank. The dam prevents the resin from overflowing in subsequent processes, and increases the degree of alignment between the display panel 201 and the touch screen panel 202 by stably supporting the touch screen panel 202 .

The control unit 70 calculates the illuminance of the transmitted ultraviolet L1 according to the illuminance of the reflected ultraviolet L2 measured by the illuminance sensor 40 . Then, the control unit 70 precisely controls the driving of the plurality of LEDs 12 based on the calculated illuminance of the transmitted ultraviolet rays L1. The ultraviolet curing device 100 can correctly realize the intended light intensity in the actual curing process, and can improve the quality of the display device by improving the curing quality of the resin 203 .

While the disclosure has been described with respect to what are presently considered to be actual exemplary embodiments, it is to be understood that the invention is not limited to the embodiments disclosed, but rather is intended to cover the various aspects included within the spirit and scope of the appended claims. Modifications and equivalent permutations.

10: Light-emitting diode (LED) module 11: Circuit board 12:LED 20: cover glass 30: shell cover 40: Illuminance sensor 50: light shielding part 51: support part 52: blocking department 60: cooling unit 70: Control unit 100: UV curing device 201: display panel 202: Touch screen panel 203: Resin L1: transmits ultraviolet rays L2: reflect ultraviolet light

FIG. 1 is a perspective view of an ultraviolet curing device according to a specific aspect of the present invention.

Fig. 2 is a perspective view showing a state in which the ultraviolet curing device shown in Fig. 1 is turned upside down.

Fig. 3 is a cross-sectional view of the ultraviolet curing device shown in Fig. 1 .

FIG. 4 is a schematic perspective view showing a temporary curing step of resin using the ultraviolet curing device shown in FIG. 1 .

30: shell cover

50: light shielding part

51: support part

52: blocking department

60: cooling unit

Claims (5)

An ultraviolet curing device, comprising: a light emitting diode (LED) module, which includes a circuit board and a plurality of light emitting diodes; a cover glass, which is arranged in front of the light emitting diode module; an illuminance sensor, It is installed on the circuit board to measure the illuminance of the ultraviolet rays reflected from the cover glass among the ultraviolet rays emitted from the plurality of light emitting diodes; detector, and shields the external light directed to the illuminance sensor; and a housing, which supports the light emitting diode module and the cover glass, wherein the plurality of light emitting diodes are arranged along the longitudinal direction of the circuit board are arranged in a straight line, and the illuminance sensor is arranged on the edge of the circuit board to leave a distance from the plurality of light emitting diodes along the width direction of the circuit board, wherein the light shielding part includes: a supporting part, which is parallel to the housing and is fixed to the housing; and a blocking portion, which is connected to the supporting portion and overlaps the illuminance sensor with a distance away from the cover glass, and wherein the blocking portion is formed to bend relative to the supporting portion at right angles. Such as the ultraviolet curing device of item 1 of the patent scope, wherein: the light-emitting diode modules are arranged in multiples, and the multiple light-emitting diode modules are arranged in a straight line along the longitudinal direction of the circuit board, and the Each of the LED modules is provided with at least one illumination sensor. Such as the ultraviolet curing device of claim 1 of the patent scope, wherein: the light shielding part is made of stainless steel. The ultraviolet curing device according to any one of items 1 to 3 in the scope of the patent application, further comprising a control unit electrically connected to the light emitting diode module and the illuminance sensor, which The control unit adjusts the current supplied to the LED module based on the illuminance of reflected ultraviolet rays measured by the illuminance sensor. For example, in the ultraviolet curing device of item 4 of the scope of the patent application, when the illuminance of the reflected ultraviolet rays measured by the illuminance sensor is lower than a predetermined reference illuminance, the control unit increases the current supplied to the light-emitting diode module amount, and when the illuminance of the reflected ultraviolet rays measured by the illuminance sensor is higher than the reference illuminance, the control unit reduces the amount of current supplied to the LED module.

Images