JP2012182281A - Light irradiation apparatus - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a light irradiation apparatus that can determine an anomalous discharge lamp by detecting a change in illuminance distribution and can maintain illuminance uniformity upon such a change in illuminance distribution.SOLUTION: The light irradiation apparatus having a light irradiation section 1 for simultaneously lighting an array of light source elements 21 each comprising a discharge lamp and a reflector to irradiate a light irradiation region with light from the light source elements 21 includes diffusion means 55 for diffusely radiating the light from the light source elements 21, and includes a light sensor 60 for detecting a light quantity distribution of diffusely scattered light reflected by the diffusion means 55. A signal detected by the light sensor 60 is fed into an image processing unit 7, and the image processing unit 7 converts an illuminance distribution on the diffusion means 55 to an illuminance distribution in the light irradiation region, and displays it on a display section or the like. When the illuminance by a specific lamp lowers, the low illuminance lamp is identified and an alarm is output, and power supplied to the lamp is increased to compensate for the change in light quantity distribution.

Description

  The present invention provides a light irradiation apparatus that performs exposure processing and the like by illuminating the illuminance distribution of light emitted from a plurality of light source elements instantaneously by arranging a plurality of light source elements using a short arc type discharge lamp in one direction and lighting them simultaneously. In particular, the light irradiation apparatus having a light detector that can detect the light intensity distribution and the integrated light amount distribution in the irradiation region can be displayed based on the output of the light detector. The present invention relates to a light irradiation device that can be made uniform.

For example, in the manufacture of a semiconductor element, a liquid crystal display substrate, or a patterned retardation film, an exposure process is performed to form a linear pattern. In this exposure process, active energy rays such as ultraviolet light are used. In order to increase mass productivity by irradiating an object to be irradiated over a wide range, it has been studied to use a light irradiation apparatus that is usually equipped with a long arc type discharge lamp.
However, since it is difficult to irradiate light parallel to each other in the longitudinal direction with a long arc type discharge lamp, there is a problem that a pattern faithful to the mask pattern and having high resolving power cannot be obtained. In addition, there is a demand for a larger irradiation area from the viewpoint of increasing the size of the liquid crystal panel and improving production efficiency.
Conventionally, the discharge lamp has been increased in size to cope with an increase in area. However, due to problems in manufacturing technology, it is becoming difficult to further increase the size of the discharge lamp.
Therefore, a light irradiation device is used in which multiple light source elements are arranged using a small short arc type discharge lamp. However, there are individual differences in illuminance and life of each short arc type lamp, and the illuminance is uniform. It is necessary to hold on.

Conventionally, in a light irradiation apparatus in which a plurality of light source elements are arranged using a short arc type discharge lamp, a method of measuring the illuminance of each lamp is performed by integrating light from a plurality of discharge lamps 101-a as shown in FIG. There is a method in which a part of light is transmitted through a light transmitting part 103-a opened in a part of the folding reflecting mirror 103 after being overlapped by 102 and measured by the illuminance measuring device 107.
In order to measure the illuminance of each light source unit 101, the illuminance information of each light source unit is measured while turning off the light source unit 101 one by one when turning off the light source unit 100, and the illuminance information is stored in the storage means 106-c. Record.
By this method, the illuminance value of each light source unit 101 can be measured (see, for example, Patent Document 1).

  Further, as a method for measuring the illuminance distribution in a light irradiation apparatus in which a plurality of light source elements are arranged using a short arc type discharge lamp, a method shown in FIG. 24 is known. As shown in the figure, the optical sensor 115 is disposed on the XYZ stage 117, and the illuminance is measured while scanning the optical sensor 115 in the direction in which the illumination system units 111-a are arranged. And the illumination intensity distribution of the illumination optical system 111 can be measured by measuring the change of illumination intensity (for example, refer patent document 2).

JP 2010-034293 A JP-A-10-284401

In the measurement method of Patent Document 1, the illuminance measurement device 107 detects a value obtained by adding the light of a plurality of light source units 101. For this reason, in order to measure the value of an individual light source unit, when the light source unit 100 is turned off, the change in illuminance must be recorded while turning off the light source unit one by one.
When the apparatus is in operation, the illuminance of each illuminance unit cannot be measured, and the illumination system unit must be turned off once for measurement, which takes time. In addition, this method is effective only for an optical system that uses an integrator or the like to create a secondary light source.

In the method of Patent Document 2, the illuminance distribution on the XYZ stage 117 can be measured by scanning the optical sensor 115 while the illumination optical system 1 is turned on.
Therefore, the substrate 116 must be removed from the XYZ stage 117 when performing measurement. When the substrate is in the form of a film, it cannot be easily removed. Therefore, the illuminance measurement is limited to replacing the film-like substrate.
For this reason, measurement cannot be performed while the apparatus is in operation, and an illuminance distribution cannot be controlled by detecting an abnormality during operation of the apparatus.
Further, in the method of measuring while scanning one optical sensor 115, it is very time consuming because it is necessary to increase the number of measurement points when measuring a detailed illuminance distribution. Furthermore, since the optical sensor 115 is exposed to strong light from the illumination light source during measurement, the temperature of the optical sensor rises. Since the measurement sensitivity of the optical sensor changes depending on the temperature, it is impossible to accurately measure the illuminance distribution.
In order to measure an accurate illuminance distribution, it is necessary for the optical sensor to simultaneously measure at the same temperature.

Furthermore, in the case of a light irradiation device in which a plurality of light source elements are arranged using a short arc type discharge lamp, the cause of the decrease in illuminance is not only the decrease in illuminance of individual light source elements, but also the illuminance of an arbitrary light source element. In some cases, the optical axis may be shifted with respect to other light source elements without being lowered.
In this case, in order to recover the reduced illuminance, increasing the current value input to the discharge lamp not only deteriorates the illuminance distribution but also decreases the life of the discharge lamp or causes the device to malfunction. Become.
For this reason, it is desirable not only to measure the illuminance distribution, but also to grasp the cause of fluctuations in illuminance based on the measurement result and to take appropriate measures based on this.
The present invention is based on the above circumstances, and in a light irradiation apparatus in which a plurality of light source elements are arranged using a short arc type discharge lamp as a light source, fluctuations in illuminance distribution of light emitted from the plurality of light source elements are batched. It is possible to detect and display a defective light source element such as a discharge lamp with reduced brightness, and the illuminance uniformity when the illuminance distribution fluctuates in the light irradiation area It is providing the light irradiation apparatus which can achieve.

In the present invention, a light source element composed of a short arc type discharge lamp and a reflector that reflects light from the discharge lamp that is disposed around the discharge lamp is arranged in one direction and simultaneously lit, and the light from the light source element is emitted. In a light irradiation apparatus that performs exposure processing by irradiating the light irradiation region, the light irradiation device is provided in a light arrival region of light from the light source element, and provided with a diffusing unit that diffuses and emits the light from the light source element A light amount detecting means in which a plurality of light detecting elements for detecting the light amount (light intensity) of the diffuse scattered light reflected by the diffusing means is provided.
The light quantity detection means receives diffuse scattered light emitted from the light source element and reflected by the diffusion means, but the light quantity (light intensity) detected at each position of the light quantity detection means is the light intensity to the light quantity detection means. The illuminance at each position on the light irradiation region irradiated with the light emitted from the light source element is not necessarily accurately reflected by the incident angle, the reflection characteristic of the diffusion plate, and the like. For example, even if the scattered light has the same intensity, the scattered light of the light incident obliquely on the light quantity detection means is measured lower than the scattered light incident from the front of the light quantity detection means.
Therefore, in the present invention, the light amount detected at each position on the light amount detection unit is associated with the illuminance at each position in the light irradiation region irradiated with the light emitted from the light source element, and each position on the light amount detection unit Means are provided for converting the amount of light into a signal representing illuminance fluctuation at each position of the light irradiation region.
As a result, a signal corresponding to the illuminance distribution in the light irradiation region can be obtained by the output of the light amount detecting means, and the fluctuation of the illuminance distribution can be detected.
Note that the illuminance is a physical quantity representing the brightness of light irradiated on the light irradiation region or the like. There are finite sizes of light detecting elements to be measured. For example, when measuring with a rectangular light detecting element arranged with its long side parallel to the transport direction, the amount to be measured is the integrated light quantity, etc. Although it may be called by another name, in this specification, the physical quantity indicating the brightness measured by the light detection element is generically expressed as illuminance.

The process of converting the light quantity at each position on the light quantity detection means into a signal representing the illuminance fluctuation at each position of the light irradiation area can be performed as follows, for example.
Prepare in advance conversion ratio data for converting the light quantity at each position on the light quantity detection means into a signal representing the illuminance at each position in the light irradiation area, and using this conversion ratio data, A signal representing the illuminance fluctuation at each position in the light irradiation region is calculated from the amount of the diffuse scattered light at each position.
The amount of light at each position on the light amount detection means detected when the discharge lamp of the light source element array is first turned on is stored as reference light amount data, and the amount of diffuse scattered light at each position on the light amount detection means And the signal showing the illumination intensity fluctuation | variation of each position in a light irradiation area | region is calculated from the said reference | standard light quantity data.

By outputting and displaying the variation in the illuminance distribution thus detected, the variation in the illuminance distribution of the light emitted from the plurality of light source elements can be monitored. Further, when it is detected from the fluctuation of the illuminance distribution that the illuminance of light emitted from a specific light source element is reduced, for example, the power supplied to the discharge lamp of the light source element is increased to reduce the illuminance. Can be compensated.
As the diffusing means, a diffusing element that diffuses and reflects light may be provided in the optical path between the light source element and the light irradiation region, but the fluctuation of the illuminance distribution is detected even while the apparatus is in operation. If desired, use a mask or the like provided in the optical path as a diffusing means, or use an optical element such as a condensing member provided in the optical path as a cold mirror on the back side of the cold mirror. A diffusing unit may be provided, and the light transmitted through the cold mirror may be reflected by the diffusing unit and guided to the light amount detecting unit.

Based on the above, in the present invention, the above-described problem is solved as follows.
(1) Light having a light source element array in which a plurality of light source elements each including a short arc type discharge lamp and a reflector that reflects light from the discharge lamp that is disposed so as to surround the discharge lamp are arranged in one direction. The light emitting unit is disposed in the light arrival region of the light from each light source element, diffuses the diffused light from the light source element and radiates, and receives the diffuse scattered light from the diffuser and receives each received light A light irradiation apparatus comprising: a light amount detection unit including a plurality of light detection elements that detect a light amount of the diffuse scattered light at a location; and an image processing unit that processes an output of the light amount detection unit. The unit is associated with each position on the light quantity detection means to each position in the light irradiation area where the light emitted from the light source element is irradiated, and the light quantity at each position detected by the light quantity detection means. Provided a conversion processing unit for converting the signal representative of the change of light intensity at each position in the optical irradiation region, and means for outputting a signal representative of the amount of fluctuation of the position of the light irradiation area obtained by the conversion processing unit.
(2) In the above (1), the image processing unit is provided with display processing means for causing the display unit to display a signal representing the light amount fluctuation obtained by the conversion processing unit in association with the position of the light irradiation region.
(3) In the above (1) and (2), a light quantity fluctuation monitoring means for monitoring a signal representing a light quantity fluctuation at each position of the light irradiation area obtained by the conversion processing unit in the image processing unit, and each light source element A power supply control means for controlling the power supplied to each light source element from a power supply device that supplies power for lighting the discharge lamp of the light source. When a decrease in the light amount of the discharge lamp of a specific light source element is detected from the signal representing the light source element, the power supply control means controls the power supply device that supplies power to turn on the discharge lamp of each light source element. Then, the electric power supplied to the discharge lamp whose light quantity has decreased is increased, and the light quantity of the discharge lamp is increased.
(4) In the above (1), (2) and (3), the image processing unit converts the light quantity at each position on the light quantity detection means into a signal representing the light quantity at each position in the light irradiation region. The conversion processing unit reads the conversion ratio data from the memory and stores the light quantity of the diffuse scattered light at each position on the light quantity detection means and the conversion ratio stored in the memory. From the data, a signal representing the light amount fluctuation at each position in the light irradiation region is calculated.
(5) In the above (1), (2), and (3), the image processing unit detects each position on the light amount detection means detected when the discharge lamp of the light source element array of the light irradiation device is first turned on. The conversion processing unit includes the amount of diffuse scattered light at each position on the light amount detection unit and the reference light amount data stored in the memory. A signal representing the light amount fluctuation at each position in the light irradiation region is calculated.

In the present invention, the following effects can be obtained.
(1) A diffusing unit that diffuses and emits light from the light source element is provided, the light amount of the diffusely scattered light at each location on the diffusing unit is detected by the light amount detecting unit, and at each position on the light amount detecting unit Since the amount of light is converted into a signal representing the illuminance fluctuation at each position in the light irradiation area and output, the fluctuation in the illuminance distribution of the light emitted from the plurality of light source elements is It is possible to monitor simultaneously without illuminating the light source and observing fluctuations in illuminance or scanning the optical sensor.
For this reason, it is possible to easily measure the illuminance distribution in a short time, the time required for the illuminance distribution measurement can be shortened, and efficient operation of the facility is enabled.
In addition, by displaying a signal representing the illuminance fluctuation at each position in the light irradiation region on the display unit in association with the position of the light irradiation region, it is possible to monitor which light source element has a reduced light amount.
(2) A light amount fluctuation monitoring means for monitoring a signal representing illuminance fluctuation at each position in the light irradiation area is provided, and a discharge of a specific light source element of the light source elements is performed by a signal representing illuminance fluctuation at each position in the light irradiation area When a decrease in the illuminance of the lamp is detected, the power supplied to the discharge lamp is increased to compensate for the decrease in the illuminance, thereby preventing a decrease in performance such as a decrease in the illuminance of the light source device and preventing a large number of defective products from being generated. be able to.
(3) Conversion ratio data for converting the light quantity at each position on the light quantity detection means into a signal representing the illuminance at each position in the light irradiation region is provided, and the diffuse scattered light at each location on the light quantity detection means A signal representing the illuminance fluctuation at each position in the light irradiation area is calculated relatively easily by calculating a signal representing the illuminance fluctuation at each position in the light irradiation area from the light amount and the conversion ratio data stored in the memory. Can be obtained.
(4) The light quantity at each position on the light quantity detection means detected when the discharge lamp of the light source element array of the light irradiation device is first turned on is stored as reference light quantity data, and at each location on the light quantity detection means. By calculating a signal representing illuminance fluctuation at each position in the light irradiation region from the light amount of the diffuse scattered light and the reference light amount data stored in the memory, the discharge lamp of the light source element array was first turned on. It is possible to grasp how much the illuminance distribution has changed compared to the illuminance distribution at that time. Further, it is possible to easily detect a decrease in illuminance of the light source element, a deviation of the optical axis of the light source element, and the like, and it is possible to accurately determine whether or not a lamp or lamp unit needs to be replaced.

It is a figure which shows schematic structure of the light irradiation apparatus of the Example of this invention. It is side surface sectional drawing which cut | disconnected the light irradiation part shown in FIG. 1 by the AA line. It is the figure which looked at the light irradiation part shown in FIG. 1 from the back side of the condensing member. It is an idea figure which shows the relationship between the measurement location on a diffusion plate, and the image receiving location of a two-dimensional area sensor. It is an idea figure which shows the relationship between the measurement location on a diffusion plate, and the image receiving location of a line sensor. It is a figure which shows the structural example in the case of providing the diffusing plate in the back side of a condensing member, and detecting the light which permeate | transmitted the condensing member. It is a figure which shows the structural example at the time of providing two optical sensors. It is a functional block diagram of the image processing unit in the light irradiation apparatus of the 1st Example of this invention. It is a flowchart which shows the process sequence of the image processing unit in the light irradiation apparatus of 1st Example of this invention. It is a figure explaining an example of the correspondence of the pixel position of each detection element of an optical detection element array, and an irradiation field position. It is a figure which shows an example of conversion ratio data (correction coefficient). It is a figure which shows the light quantity distribution detected by the photon detection element array, and the illumination intensity distribution after converting with the said conversion ratio data. It is a figure explaining the conversion process in a 1st Example. It is a figure which shows the illumination intensity change when the illumination intensity of a specific lamp falls. It is a functional block diagram of the image processing unit in the light irradiation apparatus of the 2nd Example of this invention. It is a flowchart which shows the process sequence of the image processing unit in the light irradiation apparatus of the 2nd Example of this invention. It is a figure explaining the conversion process in a 2nd Example. It is a figure which shows the illumination intensity maintenance factor when the illumination intensity of a specific lamp falls. It is a functional block diagram of the image processing unit in the light irradiation apparatus of the 3rd Example of this invention. It is a flowchart which shows the process sequence of the image processing unit in the light irradiation apparatus of the 3rd Example of this invention. It is a functional block diagram of the image processing unit in the light irradiation apparatus of the 4th Example of this invention. 10 is a flowchart showing a processing procedure of an image processing unit in the light irradiation apparatus of the fourth embodiment of the present invention. It is the schematic which shows an example of the conventional light irradiation apparatus. It is the schematic which shows another example of the conventional light irradiation apparatus.

FIG. 1 is a diagram showing an overall schematic configuration of a light irradiation apparatus according to an embodiment of the present invention, and FIG. 2 is a side sectional view of the light irradiation unit of FIG. FIG. 3 is a view of the light irradiation unit shown in FIG. 2 as seen through the light source side from the back side of the light collecting member 40.
The light irradiation apparatus of the present invention is used, for example, for manufacturing a patterned retardation film. As shown in FIG. 1, a light emitting unit 10 including a light collecting member 40 and a light emitting unit 10 are provided. The light irradiation part 1 provided with the mask 45 which shapes the light from a stripe shape, the image processing unit 7, and the power supply part 9 which supplies electric power to the lamp | ramp of the light irradiation part 1 are comprised. As shown in FIG. 2, a transport unit 50 is provided below the mask 45, the irradiated object W is transported by the transport unit 50, and the irradiated object W is irradiated with light emitted from the light irradiation unit 1. The
1 and 2, a diffusing plate 55 for measuring the illuminance distribution is inserted on the light incident side of the mask 45. This will be described later.

The light emitting unit 10 includes a light source element array 20 composed of a plurality of light source elements 21 and a light condensing member (cylindrical) that condenses light from the light source element array 20 in a line extending in one direction in which the light source elements 21 are arranged. Condensing mirror) 40 and these are housed in the lamp house 11.
A light emitting opening 12A extending in one direction along the longitudinal direction of the light collecting member 40 is formed below the light collecting member 40 of the lamp house 11, and the lower wall on which the light emitting opening 12A is formed. The diffused light incident opening 12B for allowing the diffused scattered light reflected in the light arrival region irradiated with the light emitted from the light emitting unit 10 described later to enter the lamp house 11 at the position on the back side of the light collecting member 40. Is formed. A window plate member 13 made of, for example, quartz glass is provided so as to cover the light emitting opening 12A.

In the light emitting unit 10, the light source elements 21 are arranged in one direction (a direction perpendicular to the paper surface in FIG. 2; hereinafter, this direction is also referred to as “X direction”). Is done. Each light source element 21 in the light source element array 20 includes a short arc type discharge lamp 30 and a reflector 22 arranged so as to surround the discharge lamp 30 and reflecting light from the discharge lamp 30.
As the discharge lamp 30, for example, an ultra-high pressure mercury lamp that emits ultraviolet light having a wavelength of 270 to 450 nm with high efficiency can be used. The discharge lamp 30 includes a light-emitting portion and a light-emitting tube having a rod-shaped sealing portion that is continuous at both ends of the light-emitting portion. A pair of electrodes 35 are disposed in the light-emitting tube so as to face each other. , Rare gas and halogen are enclosed. In such a discharge lamp 30, the distance between the pair of electrodes is, for example, 0.5 to 2.0 mm, and the amount of mercury enclosed is, for example, 0.08 to 0.30 mg / mm ³ .

The reflector 22 is configured by a parabolic mirror having a rotary parabolic light reflecting surface 23 centered on the optical axis C. The reflector 22 has an optical axis C of the arc tube 31 in the discharge lamp 30. It is located on the tube axis, and its focal point F is disposed at the bright spot between the electrodes in the discharge lamp 30.
The condensing member 40 is constituted by a cylindrical parabolic mirror having a parabolic light reflecting surface 41 having a cross section perpendicular to the X direction, the longitudinal direction of which extends along the X direction, and the focal point f is the irradiation object W. It is arrange | positioned so that it may be located on the surface of.
The condensing member 40 may be, for example, a cold mirror provided with a wavelength selective coating that reflects only ultraviolet light having a target wavelength and transmits unnecessary visible light and infrared light.

The mask 45 has a rectangular plate shape that is long in the X direction, and is disposed below the light collecting member 40 along a plane perpendicular to the optical axis L of the light reflected by the light collecting member 40. Has been. The mask 45 has a large number of linear light-shielding portions and a large number of light-transmitting portions extending in a direction perpendicular to the X direction (left and right direction in FIG. 2; hereinafter, this direction is also referred to as “Y direction”). Are arranged alternately.
For example, as shown in FIG. 2, the object to be irradiated W is transported in the Y direction by a transport unit 50 having a roller 51, and the mask 45 is disposed separately from the object W to be irradiated. The minimum gap G between the mask 45 and the irradiation object W is, for example, 50 to 1000 μm.

  In the light irradiation apparatus according to this embodiment, the diffusion plate 55 that diffuses and reflects the light from the light emitting unit 10 is the optical path of the light emitted from the light emitting unit 10, specifically, the light collecting member 40 and the mask. 45 is provided so as to freely advance and retreat in the optical path between them. The diffuser plate 55 is retracted from the light path of the light from the light emitting unit 10 when performing the light irradiation process on the irradiation object W, and also monitors the lighting state of each discharge lamp 30 described later (each discharge). When performing illuminance measurement and illuminance distribution measurement of a lamp), a plane perpendicular to the optical axis L of the reflected light by the condensing member 40 on the optical path of the light from the light emitting unit 10 by a driving mechanism (not shown). (See the diffusion plate 55 in FIGS. 1 and 2).

As such a diffuser plate 55, for example, a plate having a diffuse reflectance of 90% or more of ultraviolet light having a wavelength of 270 to 450 nm is preferably used. For example, a plate obtained by sintering fluororesin particles, for example, barium sulfate. For example, a light diffusing layer containing a light-shielding substance having a low transmittance such as that formed on a substrate can be used.
In addition, a plate coated with or mixed with a phosphor that is excited by ultraviolet rays and mainly emits light in the visible region emits light with very good diffusibility and efficiency with respect to incident light, and is therefore preferably used as a diffusion plate. be able to.

In the light irradiation apparatus of the present embodiment, when monitoring the illuminance distribution in the light irradiation region, the diffusion plate 55 is inserted into the light arrival region of the light emitted from the light emitting unit 10 as described above.
As shown in FIG. 3, on the back side of the light collecting member 40, there are a plurality of light detecting elements that receive the diffuse scattered light from the diffusion plate 55 and detect the amount of the diffuse scattered light at each received light spot. An optical sensor 60 having a built-in light detection element array (CCD camera) as a light amount detection means provided is provided, and an image of a pinhole plate or the like is formed in the diffused light incident opening 12B formed in the lamp house 11. When the optical element 65 is provided and the diffusing plate 55 is inserted, the light emitted from the light emitting unit 10 is reflected by the diffusing plate 55, and the diffused scattered light is reflected by the imaging optical element 65 of the optical sensor 60. An image is formed on the photodetecting element array.

The signal detected by the optical sensor 60 is sent to the image processing unit 7 shown in FIG.
The image processing unit 7 converts the light amount signal detected by the optical sensor 60 into a signal corresponding to the illuminance distribution signal of the light irradiation area where the irradiated object W is arranged, and displays the illuminance distribution signal on the display device, for example. Or output an alarm signal when the illuminance of a specific lamp decreases. Further, when the illuminance decreases due to deterioration of a lamp of a specific light source element 21 among the light source elements 21 constituting the light source element array 20, for example, the power supply device 9 that supplies power to the light source element 21 is controlled, Increase the power supplied to the lamp to compensate for the illuminance drop. Also, an alarm or the like is output when the illuminance distribution fluctuates due to, for example, the optical axis of the lamp deviating.

The detection element array of the optical sensor 60 is, for example, a two-dimensional area sensor or a CCD line sensor (one-dimensional line sensor) made of a CCD. As shown in FIG. 3, the diffuse scattered light at each of the plurality of measurement locations on the light diffusing surface on the diffusion plate 55 is passed through the imaging optical element 65 to each light detection element of the light detection element array of the light sensor 60. , And the amount of the diffuse scattered light is detected by each light detection element.
For example, when the light source element array 20 is composed of several tens of light source elements 21, the light detection element array of the optical sensor 60 has a resolution of 500 to 2000 pixels or more in the X-axis direction. Is used.
As the imaging optical element 65, for example, a pinhole plate obtained by drilling a thin metal plate by etching is used. Here, the opening diameter of the pinhole plate 65 is, for example, φ50 μm to φ1000 μm, and the thickness is, for example, 100 μm to 1000 μm. Alternatively, a chromium film may be deposited on glass and pin holes may be formed in the chromium film by etching.

In the light irradiation apparatus, the light emitted from the light emitting unit 10 is irradiated onto the irradiation object W conveyed in the Y direction by the conveying means 50 through the mask 45. That is, in the light emitting unit 10, the light emitted from the discharge lamp 30 of each light source element 21 in the light source element array 20 is reflected by the light reflecting surface 23 of the reflector 22 in the light source element 21, and the optical axis of the reflector 22. Parallel light along C is emitted toward the light collecting member 40.
The parallel light is reflected downward by the light reflecting surface 41 of the light condensing member 40 and is condensed into a linear shape extending in the X direction through the light emitting opening 12A formed in the lamp house 11 while being masked. 45 (the diffusion plate 55 is not inserted at this time). At this time, the light incident on the mask 45 is parallel light parallel to each other in the X direction. The light incident on the mask 45 is shaped into stripes by the light shielding portion and the light transmitting portion of the mask 45 and covered. By irradiating the irradiated object W, a striped light irradiation region corresponding to the pattern of the light shielding part and the light transmitting part in the mask 45 by the light emitting part 10 is formed on the surface of the irradiated object W where the roller 51 contacts. Is formed.

On the other hand, when monitoring the illuminance of each discharge lamp 30 in the light emitting unit 10 and the illuminance distribution in the light irradiation region by the light emitting unit 10 at the start of work inspection or at the end of the day's work, for example, the diffusion plate 55 Is inserted and disposed on the optical path between the light condensing member 40 and the mask 45 by an appropriate driving mechanism (not shown). In this state, the light emitted from the light emitting unit 10 is applied to the diffusion plate 55.
At this time, the light irradiated to the diffusion plate 55 is parallel light parallel to each other in the X direction, and a band-shaped light irradiation region by the light emitting unit 10 is formed on the light diffusion surface of the diffusion plate 55. As shown in FIG. 4, the light applied to the diffusion plate 55 is diffusely reflected by the light diffusion surface 55A, and the diffuse scattered light from each measurement location (P11 to P1m-Pn1 to Pnm) is converted into an imaging optical element. The light is incident on the light detection element array 61 of the optical sensor 60 via the (pinhole plate) 65.
FIG. 4 shows a case where a two-dimensional area sensor (CCD) is used as the light detection element array 61 of the light sensor 60. As shown in FIG. 4, each of the light detection elements on the light receiving surface of the light detection element array 61 is shown. An image is formed as a two-dimensional light quantity distribution image of the light irradiation area LA by the light emitting unit 10 at the image receiving positions (D11 to D1m-Dn1 to Dnm) corresponding to the measurement location. Then, each light detection element in the light detection element array 61 detects the amount of diffuse scattered light at each corresponding measurement location.
If a two-dimensional area sensor is used as the light detection element array 61, it is possible to detect a light amount distribution in the Y direction (light intensity distribution of Dk1 to Dkm (k = 1 to n)) as shown in FIG. Yes, by integrating the light amount distribution in the Y direction, the integrated light amount in the conveyance direction of the irradiated object can be obtained.

As the light detection element array 61, a line sensor may be used instead of the two-dimensional area sensor (CCD).
When the line sensor is used, the correspondence between the measurement points on the diffusion plate 55 and the individual light detection elements on the light receiving surface of the light detection element array 61 is as shown in FIG. That is, the diffuse scattered light of each of the plurality of measurement locations (P1, P2,..., Pn−1, Pn) on the light diffusion surface on the diffusion plate 55 is passed through the imaging optical element 65 to the light detection element array 61. The light quantity of the diffuse scattered light is detected by each light detection element.
In this case, since the light detection sensors are arranged one-dimensionally, the integrated light quantity cannot be obtained, but if a rectangular sensor whose light receiving surface of the light detection element is long with respect to the transport direction is selected, a measured value is obtained. Is the integrated light quantity.

Note that the optical sensor 60 including the photodetecting element array 61 and the imaging optical element 65 is not necessarily arranged in the lamp house 11 as shown in FIG. 2, and may be arranged outside the lamp house 11. In this case, as the imaging optical element, an imaging lens that forms an image of diffuse scattered light on the light diffusion surface of the diffusion plate 55 on the light detection element of the optical sensor 60 can be used.
Further, as described above, by using a cold mirror as the condensing member 40, by detecting the diffuse scattered light of visible light or infrared light that is transmitted through the condensing member 40 and is unnecessary for the treatment of the irradiated object, You may make it acquire the illumination distribution in a light irradiation area | region.

FIG. 6 shows a configuration example in the case of detecting diffused scattered light of visible light or infrared light transmitted through the light collecting member 40.
The light collecting member 40 has a wavelength selective coating that reflects ultraviolet light (270 to 340 nm) having a wavelength necessary for processing the irradiated object and transmits light having other wavelengths (for example, near ultraviolet light or visible light). As shown in the figure, a diffusion plate 55 that diffuses and reflects the transmitted light is disposed on the optical path of the transmitted light of the light collecting member 40 on the back side of the light collecting member 40. As this diffusing plate 55, for example, a plate having a diffuse reflectance of visible light having a wavelength of 350 to 700 nm of 90% or more is used.
The diffusing plate 55 is provided in a state where the light diffusing surface is inclined with respect to the optical axis of the transmitted light so that the light diffusing surface faces obliquely upward, and the diffuse scattered light at each of the plurality of measurement locations on the light diffusing surface of the diffusing plate 55 The light is incident on the photodetecting element array 60 via the element 65, and the amount of light is detected. Other configurations are the same as those shown in FIG. 2, and the same components are denoted by the same reference numerals.
If comprised in this way, as FIG. 2 demonstrated, since the light quantity can be detected, without inserting a diffuser plate in the optical path between the condensing member 40 and a light irradiation area | region, the apparatus is operated. In the meantime, it is possible to detect fluctuations in the illuminance distribution.

3 shows the case where one optical sensor 60 is used, the illuminance distribution in a wider area is measured using a plurality of optical sensors 60 than in the case where one optical sensor 60 is used. You may do it.
FIG. 7 shows a case where two optical sensors are used, and optical sensors 60 a and 60 b are arranged in the X direction in the lamp house 11. Other configurations are the same as those shown in FIG. 3, and the same components are denoted by the same reference numerals.
In such a configuration, it is preferable that a part of the detectable range of the first optical sensor 60a and the second optical sensor 60b is arranged side by side so as to overlap as shown in FIG. By arranging in this way, it is possible to avoid variations in illuminance distribution measurement values due to individual differences in sensitivity with the first and second optical sensors 60a, 60b, and to obtain high reliability in detection results. Can do.

Next, an embodiment of an image processing unit that is applied to the light irradiation apparatus having the above-described configuration and monitors the fluctuation of the illuminance distribution in the light irradiation region will be described.
FIG. 8 is a functional block diagram of the image processing unit of the light irradiation apparatus according to the first embodiment of the present invention, and FIG. 9 is a flowchart showing a processing procedure in the image processing unit.
In FIG. 8, as described above, the light emitted from the discharge lamp 30 (in the figure, each lamp is described as L1 to L5) is reflected by the reflector (elliptical mirror) 22 and emitted as parallel light.
The parallel light is reflected by the light collecting member 40 and irradiated on the diffusion plate 55 (the area irradiated with light is a shaded portion in the drawing) and is diffusely reflected by the diffusion plate 55.
The light diffusely reflected by the diffuser plate 55 (described as SL1... SL5 for each lamp in FIG. 8) is detected by an optical detection element array 61 by an imaging optical element 65 such as a lens unit or a pinhole built in the optical sensor 60. On top of this, light of a light amount corresponding to the illuminance distribution on the diffusion plate 55 is imaged. As described above, a two-dimensional area sensor (CCD) or a line sensor can be used as the photodetecting element array 61. In the following embodiments, a case where a two-dimensional area sensor is used will be described.

A signal corresponding to the amount of light detected by the optical sensor 60 is sent to the image processing unit 7. As shown in FIG. 8, the image processing unit 7 includes a processing unit 71, a storage unit 72, a display unit 73, an alarm unit 74, and the like.
The storage unit 72 includes position association data 72a for associating a signal corresponding to the amount of light detected by the optical sensor 60 with each position in a light irradiation region irradiated with light emitted from the light source element 21, and light amount detection means. The conversion ratio data 72b for converting the amount of light at each of the above positions into a signal representing the illuminance fluctuation at each position of the light irradiation region, the illuminance fluctuation threshold data 72c indicating the limit value of the illuminance fluctuation, and the use of the lamp Stored is lamp life guarantee time data 72d corresponding to the accumulated lighting time that can be guaranteed.

  The processing unit 71 performs preprocessing such as integration processing of a light amount distribution in the Y direction (line direction) (light intensity of Dk1 to Dkm (k = 1 to n in FIG. 4)) of the light amount signal transmitted from the optical sensor 60. Based on the pre-processing unit 71a that performs the processing, the position association data 72a and the conversion ratio data 72b stored in the storage unit 72, each position on the light detection element array 61 of the photosensor 60 is emitted from the light source element. A conversion processing unit 71b is provided that converts the light amount at each position on the light amount detection unit into a signal that represents the illuminance fluctuation at each position in the light irradiation region in association with each position in the light irradiation region irradiated with the light to be emitted. In addition, the illuminance fluctuation at each position of the light irradiation area converted by the conversion processing unit 71b is compared with the illuminance fluctuation threshold 72c stored in the storage unit 72 to monitor whether the illuminance has changed. And an illuminance fluctuation monitoring unit 71c that outputs an alarm signal from the alarm unit 74, and a display for performing processing for displaying the illuminance on the display unit 73 at each position of the light irradiation region converted by the conversion processing unit 71b. Based on the lamp lighting signal sent from the processing unit 71d and the power source unit 9, a lighting time monitoring unit 71e for monitoring whether the lighting time of each lamp has reached the guaranteed lamp life time 72d stored in the storage unit 72 Prepare.

Here, the conversion process in the conversion processing unit 71b will be described.
In the conversion processing, (1) processing for associating each position on the light amount detection means with each position in a light irradiation region irradiated with light emitted from the light source element, and (2) each position on the light detection element array 61 A process of converting the light quantity at the position into a signal representing the illuminance fluctuation at each position of the light irradiation region is performed. Hereinafter, the processes (1) and (2) will be described in more detail.

(1) Processing for associating each position on the light detection element array with each position of the irradiation region.
The storage unit 72 stores position association data 72a, each position on the light detection element array 61 of the light sensor 60, and each position in a light irradiation region irradiated with light emitted from the light source element. Are associated with each other by referring to the data 72a.
This is because the illuminance distribution in the light irradiation region cannot be correctly measured unless it is known which position in the light irradiation region each position on the light detection element array 61 of the optical sensor 60 corresponds to.
For example, when the direction of the light detection element array 61 (CCD camera) is slightly shifted, the position of the pixel on each detection element (CCD) corresponds to the actual irradiation region (which lamp corresponds to the irradiation position). If the information is not updated, incorrect information will be output.
Even if the pixel position of each detection element (CCD) and the irradiation area position are linear (linear function) and the scale (slope) is known, as shown in FIG. 10, the y-axis (irradiation area position) The actual position cannot be determined clearly unless the parameter corresponding to the intercept of) is determined. That is, if it is not known which position of the light-detecting element array 61 is irradiated by which lamp, the illuminance of the lamp decreases, and when adjusting the illuminance, the illuminance feedback (power adjustment) of which lamp can be performed. I don't know if I should do it.

Further, as shown in FIG. 7, even when a plurality of photosensors are arranged to irradiate a wide area, if it is not clear which position the overlapping portion corresponds to specifically, it is detected by the plurality of photosensors. The total illuminance distribution cannot be obtained by combining the light quantity data.
For the above reasons, it is desirable to provide position association data 72a for associating each position on the light detection element array 61 of the optical sensor 60 with each position in the light irradiation region irradiated with light emitted from the light source element. .
It is also conceivable that the illuminance distribution is measured in advance at the time of shipment of the apparatus, and the relationship between the position on the light detection element array 61 and the lamp 30 is associated with the position on the light detection element array 61. And the correspondence information between the irradiation area and the position of the irradiation area.

(2) Processing for converting the light quantity at each position on the light quantity detection means into a signal representing the illuminance fluctuation at each position of the light irradiation region.
As described above, the light incident on the light detection element array 61 does not accurately reflect the illuminance distribution in the light irradiation region due to factors such as the incident angle of light and the scattering characteristics of the diffusion plate 55. Compared with the diffuse scattered light from the front surface of the light detection element array, the diffuse scattered light incident from an oblique direction is measured with a low light amount even if the scattered scattered light has the same intensity.
That is, the cosine law in which the measured value changes even with the same amount of light due to the orientation angle dependency in which the intensity of the scattered light of the diffusion plate 55 varies depending on the scattering angle and the difference in the incident angle to the photodetecting element array (CCD) 61. The effect by is included.

FIG. 11 is a diagram showing an example of the correction coefficient which is the conversion ratio data 72b. The coefficient is approximately close to cos θ ² with respect to the incident angle θ to the light detection element array 61, and the effect of the cosine law is shown. Represents the correction coefficient when.
In order to determine the correction coefficient, for example, a correct illuminance distribution is measured in advance using a light receiver or the like on a mask or a work surface under irradiation conditions in the light irradiation device, and the obtained light detection element array 61 is obtained. There is a method in which a correction coefficient table is created by obtaining a ratio with the output signal.
The measurement is performed discretely, for example, and values between the measurement points are obtained by performing an interpolation process. Alternatively, a method of obtaining a correction coefficient by setting a uniform light source condition by arranging a light source of a rod-shaped lamp having a sufficient length can be used.

FIG. 12 is a diagram showing a light amount distribution detected by the light detection element array 61 and an illuminance distribution (corresponding to an illuminance distribution in the light irradiation region) after being converted by the conversion ratio data. The position in the longitudinal direction of the lamp array (the position on the light irradiation region located in front of each lamp) is shown, and L1 to L11 correspond to the peak positions of the illuminance distribution of the lamps L1 to L11. Also, the vertical axis represents the illuminance (relative value), and the light amount distribution A detected by the photodetecting element array 61 indicated by the one-dot chain line in the figure by the above conversion processing is as the illuminance distribution B indicated by the solid line in the figure. It is corrected to.
FIG. 13 is a diagram for explaining the conversion processing in the present embodiment. FIG. 13A shows light amount data (A) (light amount distribution data) detected by the light detection element array 61. This example shows a case where the illuminance is reduced in the circled region in the figure due to a decrease in the illuminance of the lamp. FIG. 5B shows the conversion ratio data (B) shown in FIG.
The conversion process is performed, for example, by dividing the light amount data (A) by the conversion ratio data (B) and calculating (A) / (B). Thereby, as shown in FIG.13 (c), the signal corresponding to the illumination distribution of a light irradiation area | region can be obtained.
By performing the conversion process in this manner, the illuminance level at the position in the lamp array longitudinal direction (position in the X direction) can be made uniform, and the portion where the illuminance has decreased can be immediately grasped.

FIG. 9 is a flowchart showing processing in the image processing unit 7. The processing in the image processing unit will be described with reference to FIG.
The processing unit 71 captures the CCD image detected by the optical sensor 60 (step S1), and the preprocessing unit 71a performs the integration process of the light amount distribution in the line direction (Y direction) as described above (step S2). Next, the conversion ratio data 72b and the position association data 72a are read from the storage unit 72, and the conversion processing unit 71b performs conversion processing as described above (steps S3 and S4).
Next, the illuminance distribution data converted by the conversion processing unit 71b is processed by the display processing unit 71d and displayed as image data on the display unit 73 (step S5). Thereby, as shown in FIG.13 (c), the fluctuation | variation of illumination intensity distribution is displayed.

The illuminance fluctuation monitoring unit 71c compares the illuminance distribution data converted by the conversion processing unit 71b with the illuminance fluctuation threshold data 72c stored in the storage unit 72, and determines whether there is an illuminance change of the specific lamp (step). S6, S7).
FIG. 14 is a diagram showing the change in illuminance when the illuminance of some lamps decreases. The horizontal axis in FIG. 14 indicates the position in the lamp array longitudinal direction (position on the light irradiation area located in front of each lamp). L1, L2, and L3 correspond to the peak positions of the illuminance distribution of the respective lamps L1 to L4. The vertical axis represents illuminance (relative value), A is detected light amount distribution data, B is illuminance threshold, and C is illuminance by each of the discharge lamps L1 to L4 provided in each light source element 21 of the light source element array 20. Show the distribution.
As shown in FIG. 14, the illuminance fluctuation monitoring unit 71c compares the converted illuminance distribution A with the illuminance threshold B, and there is a region where the illuminance is lower than the illuminance threshold B as shown by the dotted line in FIG. Then, it is determined which lamp is the cause of the decrease in illuminance, and an alarm signal is output from the alarm unit 74 (step S11). In this example, since it can be seen that the illuminance of the lamp L2 has decreased, the fact that the illuminance of the lamp L2 has decreased is output as an alarm signal.
When the illuminance reduction signal is output as an alarm signal, the light irradiation device is abnormally terminated or turned off.

The lighting time monitoring unit 71e monitors the cumulative lighting time of the lamps L1 to L5 sent from the power supply unit 9 that supplies power to the lamps L1 to L5 (step S8). Then, it is compared with the guaranteed lamp life time stored in the storage unit 72d to determine whether or not the accumulated lighting time has reached the guaranteed life (step S9). The lamp replacement warning signal is output from (step S10). Thereby, operation | movement of a light irradiation apparatus is complete | finished and it extinguishes.
If the accumulated lighting time has not reached the guaranteed life, the process returns to step S1 after a predetermined interval time and the above processing is repeated.

FIG. 15 is a functional block diagram of the image processing unit of the light irradiation apparatus according to the second embodiment of the present invention, and FIG. 16 is a flowchart showing a processing procedure in the image processing unit.
In FIG. 15, the configuration of the light irradiation unit 1 is the same as that shown in FIG. 8, and the light emitted from the discharge lamp 30 (in the figure, each lamp is denoted as L <b> 1 to L <b> 5) is a reflector (elliptical mirror) 22. The light that is reflected by and emitted as parallel light is reflected by the light collecting member 40 and irradiated onto the diffusion plate 55. The light diffusely reflected by the diffusion plate 55 is converted into light corresponding to the illuminance distribution on the light detection element array 61 by the imaging optical element 65 such as a lens unit or a pinhole built in the optical sensor 60. The intensity of the image.

A signal (light quantity) corresponding to the light intensity detected by the optical sensor 60 is sent to the image processing unit 7. The image processing unit 7 includes a processing unit 71, a storage unit 72, a display unit 73, an alarm unit 74, and the like, as shown in FIG.
In the storage unit 72, the position association data 72 a for associating the light quantity with each position in the light irradiation region, and the light detection element array 61 in a state where the illuminance of each discharge lamp 30 of the light irradiation unit 10 is not reduced. The reference light quantity data 72e, which is the light quantity data at each position on the light detection element array 61 detected by the above, the illuminance fluctuation threshold data 72c indicating the limit value of the illuminance fluctuation, and the integrated lighting time that can guarantee the use of the lamp. Lamp life guarantee time data 72d is stored.
The reference light amount data 72e is, for example, light amount data at each position on the light detection element array 61 detected when a new discharge lamp 30 is attached to the light irradiation unit 10 and the discharge lamp 30 is first turned on. The data is recorded in the storage unit 72, and this data is used as reference light amount data.

The processing unit 71 has basically the same configuration as that shown in FIG. 8, and a preprocessing unit 71 a that performs preprocessing such as integration processing on the light amount signal transmitted from the optical sensor 60 as described above, Based on the position association data 72a stored in the storage unit 72 and the reference light amount data 72e, the light emitted from the light source element is irradiated on each position on the light detection element array 61 of the photosensor 60. Corresponding to each position in the irradiation region, a conversion processing unit 71b is provided that converts the light amount at each position on the light amount detection means into a signal representing illuminance fluctuation at each position in the light irradiation region.
In addition, the illuminance fluctuation at each position of the light irradiation area converted by the conversion processing unit 71b is compared with the illuminance fluctuation threshold 72c stored in the storage unit 72 to monitor whether the illuminance has changed. And an illuminance fluctuation monitoring unit 71c that outputs an alarm signal from the alarm unit 74, and a display for performing processing for displaying the illuminance on the display unit 73 at each position of the light irradiation region converted by the conversion processing unit 71b. Based on the lamp lighting signal sent from the processing unit 71d and the power source unit 9, a lighting time monitoring unit 71e for monitoring whether the lighting time of each lamp has reached the guaranteed lamp life time 72d stored in the storage unit 72 Prepare.

  In the present embodiment, as described above, the conversion processing in the conversion processing unit 71b is performed as follows: (1) Each position on the light amount detection means is set to each position in the light irradiation region irradiated with the light emitted from the light source element. A process of associating, and (2) a process of converting the amount of light at each position on the light detection element array 61 into a signal representing illuminance fluctuation at each position of the light irradiation region. This is different from the first embodiment.

Regarding the process (1), as described above, using the position association data 72a, each position on the light detection element array 61 of the optical sensor 60 and the light emitted from the light source element are irradiated. Association with each position in the irradiation region is performed. As described above, the relationship between the position on the light detection element array 61 and the lamp may be associated with each other.
Regarding the process (2), in this embodiment, the conversion is performed as follows.
FIG. 17 is a diagram for explaining the conversion processing in the present embodiment. FIG. 17A shows light amount data (A) (light intensity distribution data) detected by the light detection element array 61. This example shows a case where the amount of light has decreased in the circled region of FIG. FIG. 4B shows reference light amount data (B).
As described above, the reference light quantity data indicates the light quantity at each position on the light detection element array 61 detected by the light detection element array 61 when the new discharge lamp 30 is attached and the discharge lamp 30 is first turned on. These are stored in the storage unit 72 as reference data.

The conversion process in this embodiment is performed, for example, by dividing the light amount data (A) by the reference light amount data (B) and calculating (A) / (B).
As a result, as shown in FIG. 17C, a signal indicating how much the light amount at which position has decreased with respect to the illuminance distribution in the light irradiation region when the discharge lamp is first turned on, that is, the light amount A signal indicating the rate of decrease (hereinafter, this signal is referred to as illuminance maintenance rate) is obtained. In the figure, the illuminance is reduced at the circled portions.
By performing the conversion process in this way, it becomes possible to immediately grasp how much the illuminance has decreased at the position in the longitudinal direction of the lamp array (position in the X direction) compared to the time when the reference light amount data was measured. .
FIG. 18 is a diagram (simulation result) showing an example of fluctuation of the illuminance maintenance ratio (ratio of decrease in illuminance). FIG. 18A shows a case where the illuminance of a specific lamp is reduced, and FIG. Indicates a case where the optical axis of a specific lamp is deviated. The horizontal axis in the figure indicates the position in the lamp array longitudinal direction (position on the light irradiation area located in front of each lamp), and L1, L2, and L3 are at peak positions of the illuminance distribution of the respective lamps L1 to L4. Equivalent to.
The vertical axis indicates the illuminance maintenance factor and illuminance (relative value), A indicates the illuminance maintenance factor data, and the solid line indicates the initial illuminance when the illuminance decreases to 0.9 compared to the initial value. The case where it falls to 0.8 compared with the value is shown. C is the illuminance by each of the discharge lamps L1 to L4 provided in each light source element 21 of the light source element array 20.

As shown in FIG. 18A, when the illuminance of the specific lamp decreases, the illuminance maintenance factor data A obtained by the above conversion is a position corresponding to the lamp with the decreased illuminance (in this example, a position corresponding to the lamp L2). ). Thereby, it can be grasped which lamp the illuminance has decreased.
Further, when the optical axis of the specific lamp (in this example, the lamp L2) is tilted, the illuminance maintenance factor data changes as shown in FIG.
That is, when the illuminance of the specific lamp decreases, the light quantity maintenance rate at the position corresponding to the center decreases as shown in FIG. 18A, but when the optical axis of the lamp deviates, the adjacent lamps By changing the degree of overlap of the amount of light, the valley and the mountain come out next to each other.
In particular, the peak positions of the valleys and the peaks occur at different positions from the front position of the lamp center. For example, it can be seen that the valley portion of the illuminance distribution occurs between L1 and L2, and the peak portion occurs between L2 and L3.
As described above, when the illuminance of a specific lamp is reduced and when the optical axis is tilted, the fluctuation state of the illuminance maintenance rate is different, so it is determined whether the illuminance of the lamp has decreased or the optical axis is tilted. be able to.

FIG. 16 is a flowchart showing a processing procedure in the image processing unit 7. The processing in the image processing unit will be described with reference to FIG. The processing in this embodiment is basically the same as FIG. 9 except that the conversion processing is different from the flowchart of FIG.
The processing unit 71 captures the CCD image detected by the optical sensor 60 (step S1), and the preprocessing unit 71a performs the integration process of the light amount distribution in the line direction (Y direction) as described above (step 2).
Next, in step S3, the reference light amount data 72e and the position association data 72a stored in the storage unit 72 are read, and the conversion processing unit 71b performs the conversion process as described above (step S4).
Next, it is determined whether or not the image capture is the capture of an image when the new lamp is attached and lighted for the first time (step S5). In the case of reading the image when it is turned on, this data is stored in the storage unit 72 as reference light amount data (step S12), and after a predetermined interval time, the process returns to step S1.
In addition, when the image is not captured when the new lamp is attached and turned on for the first time, the illuminance distribution data converted by the conversion processing unit 71b is processed by the display processing unit 71d, and the image is captured. The data is displayed on the display unit 73 (step S6). Thereby, as shown in FIG. 17C, the fluctuation of the illuminance distribution is displayed.

The illuminance fluctuation monitoring unit 71c compares the illuminance distribution fluctuation data converted by the conversion processing unit 71b with the illuminance fluctuation threshold data 72c stored in the storage unit 72, and determines whether there is an illuminance change of the specific lamp. (Steps S7 and S8).
For example, as shown in FIG. 18A, the illuminance fluctuation monitoring unit 71c determines which lamp is the cause of the decrease in illuminance when there is a region where the illuminance decreases, and the alarm unit 74 The alarm signal is output from (Step S13). In this example, since it can be seen that the illuminance of the lamp L2 has decreased, the fact that the illuminance of the lamp L2 has decreased is output as an alarm signal.
When the illuminance lowering signal is output as an alarm signal, the light irradiation device is abnormally terminated or turned off when the degree of optical axis deviation is a certain value or more.
In the illuminance fluctuation monitoring unit 71c, as shown in FIG. 18B, a valley of the illuminance distribution is generated between the specific first lamp L1 and the second lamp L2, and the peak is the first. If it occurs between the two lamps L2 and the third lamp L3, it is determined that the optical axis of the lamp L2 is shifted, and an alarm signal is output from the alarm unit 74 (step S13). Abnormal termination or turn off.

  The lighting time monitoring unit 71e monitors the cumulative lighting time of the lamps L1 to L5 sent from the power source unit 9 that supplies power to the lamps L1 to L5 as described above (step S9). Then, it is compared with the guaranteed lamp life time stored in the storage unit 72d to determine whether or not the accumulated lighting time has reached the guaranteed life (step S10). The lamp replacement warning signal is output from (Step S11). Thereby, operation | movement of a light irradiation apparatus is complete | finished and it extinguishes. If the accumulated lighting time has not reached the guaranteed life, the process returns to step S1 after a predetermined interval time and the above processing is repeated.

FIG. 19 is a functional block diagram of the image processing unit of the light irradiation apparatus according to the third embodiment of the present invention, and FIG. 20 is a flowchart showing a processing procedure in the image processing unit. This embodiment is configured to restore the illuminance distribution by increasing the power supplied to the lamp when the illuminance of the specific lamp is lowered in the first embodiment shown in FIGS. It is a thing.
In FIG. 19, the configuration of the light irradiation unit 1 is the same as that shown in FIG. 8, and the light emitted from the discharge lamp 30 (each lamp is denoted as L1 to L5 in the figure) is a reflector (elliptical mirror) 22. The light that is reflected by and emitted as parallel light is reflected by the light collecting member 40 and irradiated onto the diffusion plate 55. The light diffusely reflected by the diffusing plate 55 is reflected on the light detecting element array 61 by the imaging optical element 65 such as a lens unit or a pinhole built in the optical sensor 60, and the amount of light corresponding to the illuminance distribution on the diffusing plate 55. Forms an image.

A signal (light quantity) corresponding to the light intensity detected by the optical sensor 60 is sent to the image processing unit 7. As described above, the image processing unit 7 includes the processing unit 71, the storage unit 72, the display unit 73, the alarm unit 74, and the like. The storage unit 72 includes the position association data 72a and the conversion ratio data 72b. Illuminance fluctuation threshold data 72c and lamp life guarantee time data 72d are stored.
As shown in FIG. 8, the processing unit 71 stores the pre-processing unit 71a, the conversion processing unit 71b, the illuminance fluctuation monitoring unit 71c, the display processing unit 71d, and the lighting time of each lamp in the storage unit 72. A lighting time monitoring unit 71e for monitoring whether the lamp guaranteed lifetime 72d has been reached.
Further, in the present embodiment, the power supply control unit 71f that controls the power of the lamp to increase when the illuminance fluctuation monitoring unit 71c detects a decrease in the illuminance of the specific lamp is provided.
The power supply control unit 71f is a power supply unit that supplies power to the lamp among the power supply units PS1 to PS5 of the power supply unit 9 of the lamp (for example, in the case of the lamp L2), if the decrease in illuminance is within a power adjustable range. The power supply unit PS2) is controlled to increase the power.
When the decrease in illuminance is not within the range in which power adjustment is possible, the illuminance fluctuation monitoring unit 71 c causes the alarm unit 74 to output an illuminance decrease alarm.
Except for having the power supply control unit 71f, the configuration of the image processing unit of the present embodiment is the same as that shown in FIG. 8, and the operation of each unit is also the same.

The processing of the processing unit in the present embodiment will be described with reference to the flowchart of FIG. In addition, when the fall of the illumination intensity of a specific lamp is detected, it is the same as that of the process of FIG. 9 except for controlling that the electric power of the said lamp increases.
The processing unit 71 captures the CCD image detected by the optical sensor 60 (step S1), and the preprocessing unit 71a performs the integration process of the light amount distribution in the line direction (Y direction) as described above (step S2). Next, the conversion ratio data 72b and the position association data 72a are read from the storage unit 72, and the conversion processing unit 71b performs conversion processing as described above (steps S3 and S4).
Next, the illuminance distribution data converted by the conversion processing unit 71b is processed by the display processing unit 71d and displayed as image data on the display unit 73 (step S5). Thereby, as shown in FIG.13 (c), the fluctuation | variation of illumination intensity distribution is displayed.

The illuminance fluctuation monitoring unit 71c compares the illuminance distribution data converted by the conversion processing unit 71b with the illuminance fluctuation threshold data 72c stored in the storage unit 72, and determines whether there is an illuminance change of the specific lamp (step). S6, S7).
When there is a region where the illuminance decreases, the illuminance fluctuation monitoring unit 71c determines which lamp is the cause of the decrease in illuminance, and determines whether the illuminance decrease is within a power adjustable range. (Step S11). When the illuminance reduction can be recovered by the power adjustment, the process goes to step S13, and the power supply control unit 71f is controlled to adjust the power of the lamp.
For this power adjustment, for example, the power amount may be feedback-controlled so that the light amount distribution detected by the optical sensor 60 becomes a desired distribution, or the power adjustment amount with respect to the illuminance reduction amount is stored. The amount of power may be increased according to the amount of decrease in illuminance.
If the decrease in illuminance is not within the range that can be recovered by power adjustment, an alarm signal indicating a decrease in illuminance is output from the alarm unit 74 (step S12). When the illuminance reduction signal is output as an alarm signal, the light irradiation device is abnormally terminated or turned off.

In addition, the lighting time monitoring unit 71e monitors the integrated lighting time of the lamps L1 to L5 (step S8), and compares it with the lamp guaranteed life time stored in the storage unit 72d to determine whether the integrated lighting time has reached the guaranteed life. Whether or not (step S9), and when the integrated lighting time reaches the guaranteed life, the alarm unit 74 outputs an alarm signal for lamp replacement (step S10). Thereby, operation | movement of a light irradiation apparatus is complete | finished and it extinguishes.
If the accumulated lighting time has not reached the guaranteed life, the process returns to step S1 after a predetermined interval time and the above processing is repeated.

FIG. 21 is a functional block diagram of the image processing unit of the light irradiation apparatus according to the fourth embodiment of the present invention, and FIG. 22 is a flowchart showing a processing procedure in the image processing unit. This embodiment is configured to restore the illuminance distribution by increasing the power supplied to the lamp when the illuminance of the specific lamp decreases in the second embodiment shown in FIGS. 15 and 16. It is a thing.
In FIG. 21, the configuration of the light irradiation unit 1 is the same as that shown in FIG. 8, and the light emitted from the discharge lamp 30 (in the figure, each lamp is indicated as L1 to L5) is reflected by a reflector (elliptical mirror) 22. The light that is reflected by and emitted as parallel light is reflected by the light collecting member 40 and irradiated onto the diffusion plate 55. The light diffusely reflected by the diffusing plate 55 is reflected on the light detecting element array 61 by the imaging optical element 65 such as a lens unit or a pinhole built in the optical sensor 60, and the amount of light corresponding to the illuminance distribution on the diffusing plate 55. Forms an image.

A signal (light quantity) corresponding to the light intensity detected by the optical sensor 60 is sent to the image processing unit 7. The image processing unit 7 includes a processing unit 71, a storage unit 72, a display unit 73, an alarm unit 74, and the like, as shown in FIG.
The storage unit 72 stores position association data 72a, reference light amount data 72e, illuminance fluctuation threshold data 72c, and lamp guarantee lifetime data 72d.
As described above, the reference light amount data 72e is, for example, each position on the light detecting element array 61 detected when the new discharge lamp 30 is attached to the light irradiation unit 10 and the discharge lamp 30 is first turned on. Is stored in the storage unit 72, and this data is used as reference light amount data.

The processing unit 71 has basically the same configuration as that shown in FIG. 15, and includes a preprocessing unit 71a, a conversion processing unit 71b, an illuminance fluctuation monitoring unit 71c, a display processing unit 71d, and a lamp guaranteed lifetime 72d. Is provided with a lighting time monitoring unit 71e for monitoring whether or not
Further, in this embodiment, as described in the third embodiment, when the illuminance fluctuation monitoring unit 71c detects a decrease in illuminance of a specific lamp, power supply is controlled so that the power of the lamp increases. A control unit 71f is provided.
The power supply control unit 71f is a power supply unit that supplies power to the lamp among the power supply units PS1 to PS5 of the power supply unit 9 of the lamp (for example, in the case of the lamp L2), if the decrease in illuminance is within a power adjustable range. The power supply unit PS2) is controlled to increase the power.
When the decrease in illuminance is not within the range in which power adjustment is possible, the illuminance fluctuation monitoring unit 71 c causes the alarm unit 74 to output an illuminance decrease alarm.
Except for the provision of the power supply control unit 71f, the configuration of the image processing unit of the present embodiment is the same as that shown in FIG. 15, and the operation of each unit is also the same.

FIG. 22 is a flowchart showing a processing procedure in the image processing unit 7 of the present embodiment. Processing in the image processing unit will be described with reference to FIG. In addition, when the fall of the illumination intensity of a specific lamp is detected, it is the same as the process of FIG. 16 except for controlling so that the electric power of the said lamp increases.
The processing unit 71 captures the CCD image detected by the optical sensor 60 (step S1), and the preprocessing unit 71a performs an integration process of the light amount distribution (step S2).
Next, the process goes to step S3, where the reference light amount data 72e and the position association data 72a stored in the storage unit 72 are read, and the conversion processing unit 71b performs the conversion process as described above (step S4).
Next, it is determined whether or not this image capture is the capture of an image when a new lamp is attached and lighted for the first time (step S5), and the image capture is performed for the first time when a new discharge lamp is attached. In the case of reading the image at the time, the data is stored as the reference light quantity data in the storage unit 72 (step S13), and after a predetermined interval time, the process returns to step S1.
In addition, when the image is not captured when the new lamp is attached and turned on for the first time, the illuminance distribution data converted by the conversion processing unit 71b is processed by the display processing unit 71d, and the image is captured. The data is displayed on the display unit 73 (step S6). Thereby, as shown in FIG. 17C, the fluctuation of the illuminance distribution is displayed.

The illuminance fluctuation monitoring unit 71c compares the illuminance distribution fluctuation data converted by the conversion processing unit 71b with the illuminance fluctuation threshold data 72c stored in the storage unit 72, and determines whether there is an illuminance change of the specific lamp. (Steps S7 and S8).
When there is a region where the illuminance decreases, the illuminance fluctuation monitoring unit 71c determines which lamp is the cause of the decrease in illuminance, and determines whether the illuminance decrease is within a power adjustable range. (Step S14). If the illuminance reduction can be recovered by the power adjustment, the process goes to step S15 to control the power supply control unit 71f to adjust the power of the lamp.
If the decrease in illuminance is not within the range that can be recovered by power adjustment, an alarm signal indicating a decrease in illuminance is output from the alarm unit 74 (step S16). When the illuminance reduction signal is output as an alarm signal, the light irradiation device is abnormally terminated or turned off.
When the light quantity fluctuation monitoring unit 71c determines that the optical axis of the lamp is deviated as described with reference to FIG. 18B (step S9), it outputs an alarm signal from the alarm unit 74 (step S17). ), The light irradiation device is abnormally terminated or turned off.

  The lighting time monitoring unit 71e monitors the integrated lighting time of the lamps L1 to L5 sent from the power supply unit 9 that supplies power to the lamps L1 to L5 as described above (step S10). Then, it is compared with the guaranteed lamp life time stored in the storage unit 72d to determine whether or not the accumulated lighting time has reached the guaranteed life (step S11). The lamp replacement warning signal is output from (Step S12). Thereby, operation | movement of a light irradiation apparatus is complete | finished and it extinguishes. If the accumulated lighting time has not reached the guaranteed life, the process returns to step S1 after a predetermined interval time and the above processing is repeated.

In the description of the above embodiment, the light amount distribution sent in the Y direction (line direction) is performed on the light amount signal sent from the optical sensor 60, and the fluctuation of the illuminance distribution is displayed in the X direction. Not only the illuminance distribution in the X direction but also the illuminance distribution in the Y direction may be displayed using the data before processing.
Specifically, the illuminance distribution in the X direction and the Y direction is displayed in the form of a contour map, for example. If the illuminance distribution is displayed in this way, the entire state can be seen at a glance, so that it is easy to confirm an abnormality.
In the above description, the case where a two-dimensional area sensor is used as the light detection element array 61 has been described. However, the line sensor shown in FIG. 5 can be used.
When a line sensor is used as the photodetecting element array 61, the integration process in the line direction in step S2 is not necessary in the flowchart of the above embodiment, but other processes are the same as described in the above embodiment. It is.
In the above embodiment, the case where the diffusion plate is placed in the irradiation area has been described. However, the visible light emitted from the fluorescent plate may be measured and the light from the mask may be measured without placing the diffusion plate or the like. Scattered light may be measured. Further, as described with reference to FIG. 6, a cold mirror is used as the condensing member 40, and the diffused scattered light of visible light or infrared light that has passed through the condensing member 40 and is unnecessary for the treatment of the irradiated object. By detecting, the illuminance distribution in the light irradiation region may be acquired.
When measuring the scattered light from the mask, the reflectance decreases depending on the location and the measurement accuracy decreases, but it is possible to measure in real time while performing exposure. Similarly, when a cold mirror is used as the condensing member and the illuminance distribution in the light reaching region is obtained by detecting the diffuse scattered light of visible light or infrared light transmitted through the condensing member, exposure is similarly performed. It becomes possible to measure in real time while performing.

DESCRIPTION OF SYMBOLS 1 Light irradiation part 7 Image processing unit 9 Power supply part 10 Light output part 11 Lamp house 12A Light output opening 12B Diffuse light incident opening 13 Window plate member 20 Light source element array 21 Light source element 22 Reflector (elliptical mirror)
30 Short arc type discharge lamp 40 Condensing member (cylindrical condensing mirror)
45 Mask 50 Conveying means 55 Diffuser plate 60 Optical sensor 61 Photodetecting element array 65 Imaging optical element 65
71 processing unit 71a pre-processing unit 71b conversion processing unit 71c illuminance fluctuation monitoring unit 71d display processing unit 71e lighting time monitoring unit 71f power supply control unit 72 storage unit 72a position association data 72b conversion ratio data 72c illuminance fluctuation threshold data 72d lamp guarantee lifetime Time data 72e Reference light quantity data 73 Display unit 74 Alarm unit

Claims (5)

A light emitting unit having a light source element array in which a plurality of light source elements each including a short arc type discharge lamp and a reflector that reflects light from the discharge lamp disposed so as to surround the discharge lamp are arranged in one direction; ,
A diffusing means for diffusing and radiating the light from the light source element, disposed in the light arrival area of the light from each light source element;
A light amount detection means comprising a plurality of light detection elements for receiving the diffuse scattered light from the diffusion means and detecting the amount of the diffuse scattered light at each received spot;
A light irradiation device comprising an image processing unit for processing the output of the light amount detection means,
The image processing unit associates each position on the light amount detection unit with each position in a light irradiation region irradiated with light emitted from the light source element, and converts the light amount at each position on the light amount detection unit to the light. A conversion processing unit that converts the light intensity variation at each position of the irradiation region into a signal,
A light irradiation apparatus comprising: means for outputting a signal representing a light amount fluctuation at each position of the light irradiation region obtained by the conversion processing unit. The light irradiation device includes a display unit, and the image processing unit causes the display unit to display a signal representing the light amount fluctuation obtained by the conversion processing unit in association with the position of the light irradiation region. The light irradiation apparatus according to claim 1, further comprising means. The light irradiation device includes a power supply device that supplies power to light a discharge lamp of each light source element of the light irradiation device,
The image processing unit further includes a light amount variation monitoring unit that monitors a signal representing a light amount variation at each position of the light irradiation region obtained by the conversion processing unit, and power supplied from the power supply device to each light source element. Power supply control means for controlling,
The light amount fluctuation monitoring means is configured such that when the light quantity reduction of the discharge lamp of a specific light source element among the light source elements is detected by a signal representing the light quantity fluctuation at each position of the light irradiation region, the power supply control means The light irradiation apparatus according to claim 1 or 2, wherein the apparatus is controlled to increase the power supplied to the discharge lamp having the reduced light quantity, thereby increasing the light quantity of the discharge lamp. The image processing unit has a memory storing conversion ratio data for converting the light quantity at each position on the light quantity detection means into a signal representing the light quantity at each position in the light irradiation region,
The conversion processing unit reads conversion ratio data from the memory, and calculates each position in the light irradiation region from the amount of diffuse scattered light at each location on the light amount detection means and the conversion ratio data stored in the memory. The light irradiation apparatus according to claim 1, wherein a signal representing a change in the amount of light is calculated. The image processing unit has a memory that stores, as reference light amount data, the light amount at each position on the light amount detection means detected when the discharge lamp of the light source element array of the light irradiation device is first turned on.
The conversion processing unit calculates a signal representing a light amount variation at each position in the light irradiation region from the light amount of the diffuse scattered light at each location on the light amount detection unit and the reference light amount data stored in the memory. The light irradiation apparatus according to claim 1, 2 or 3.

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