JPH11142285A - Micro-lens inspecting device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a micro-lens inspecting device in which the inspection of micro-lenses is improved. SOLUTION: A parallel light incidence means 11 makes parallel light L2 incident on a micro-lens 12. An inspection processing means 14 captures transmitted light L3 transmitted through the micro-lens 12, discriminates only a specific part with a significant difference from other parts of the micro-lens from the measured values of the transmitted light L3, and determines it as failure.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a microlens inspection apparatus, and more particularly to a microlens inspection apparatus for improving the inspection of microlens formation.

[0002]

2. Description of the Related Art At present, a liquid crystal display (LCD) is required to have higher luminance and higher resolution (higher definition) than ever before. In particular, demand for transmissive LCDs for projector applications is increasing. In this trend, projectors are required to be reduced in size and weight, and small, high-brightness, high-definition LCDs are more and more required to satisfy these requirements.

Conventional LCDs use flat glass or a transparent material similar to glass on the opposite side of the TFT substrate. This glass had a uniform material, a uniform refractive index and a uniform thickness everywhere.

On the other hand, in recent years, in order to realize a small-sized, high-brightness, high-definition LCD, a plurality of materials having different refractive indexes are used as opposed substrates instead of using a uniform transparent flat substrate such as conventional glass. To condense the light to a predetermined location,
A method using a so-called microlens (microlens substrate) has been put to practical use.

FIG. 9 is a diagram showing a cross section of a microlens substrate. The microlens substrate 100 forms a microlens having a shape of B on a microlens substrate of A made of, for example, quartz by filling a resin, for example. Then, for example, a cover glass C for protecting the microlens with quartz or the like is used.

Each of the materials A, B, and C has an optimum refractive index and hardness dimension shape as a component of the LCD. In general, if the refractive index of A is n, the refractive index of B is n1, and the refractive index of C is n2, then n ≠ n1, and n2 is n,
It is arbitrary for n1.

FIG. 10 shows that the microlens substrate 100 is LC
It is a section schematic diagram when used for D. The sectional structure of the LCD 200 is, in order from the top, a polarizing plate 201, a microlens substrate 100, an ITO (Indium Tin Oxide) 202, a liquid crystal 2
03, ITO204, TFT205, TFT substrate 20
6. It is composed of a polarizing plate 207.

When guiding incident light to a desired location using such a microlens, a difference in the refractive index between the microlens and the microlens substrate is used. Then, the incident light is guided to the opening of the TFT, thereby realizing high brightness of the LCD.

However, if the microlens is not formed to a predetermined size, the incident light cannot be guided to a predetermined location, so that it is impossible to achieve high brightness of the LCD. In addition, since the incident light is guided to a location other than the predetermined location,
Causes the image quality to deteriorate.

FIG. 11 is a diagram showing microlens defects. (A) shows the irregular shape of the microlens, (B) shows that the microlens is not filled with resin, and (C) shows that the foreign matter is mixed.
The microlens 101 shown in (A) is an abnormality in which the microlens was not formed in a correct shape. The microlens 102 in FIG. 9B is a microlens substrate (A in FIG. 9).
Is not sufficiently filled with the resin (B in FIG. 9) to form a gap. The microlens 103 shown in FIG. 3C is defective when a foreign substance is mixed in the resin forming the microlens.

Therefore, the inspection of the correct formation of the microlenses and the inspection accuracy are very important matters. FIG. 12 is a diagram showing a conventional microlens inspection method.

Conventionally, the inspector 1 positioned opposite to the light source D holds the microlens 100 to be inspected with his / her hand or a substitute thereof, and moves the microlens 100 delicately by hand or the like, and While looking closely, the defect and defect of the microlens 100 were searched for and inspected using the reflected light from the microlens 100 from the light source D.

[0013]

However, in the conventional inspection method as described above, since a human visual inspection using a difference in the appearance of reflected light due to a microlens defect or a foreign matter is often missed. Therefore, there have been problems in terms of health, such as low productivity or physical fatigue of the examiner 1 and abnormal visual acuity.

Further, even when a defect occurs, the defect cannot be quantitatively evaluated, and there has been a problem that the efficiency is low in terms of improvement in microlens yield and production management. The present invention has been made in view of such a point, and an object of the present invention is to provide a microlens inspection apparatus which improves the inspection of microlens formation.

[0015]

According to the present invention, there is provided a microlens inspection apparatus for improving the inspection of microlens formation in order to solve the above-mentioned problems. Incorporating the transmitted light transmitted through the microlens, only a specific portion of the microlens from the measured value of the transmitted light, selecting the portion having a significant difference than the other, inspection processing means to determine a defect, A microlens inspection apparatus characterized by having:

Here, the parallel light incident means makes parallel light incident on the microlens. The inspection processing means takes in the transmitted light transmitted through the microlens, selects only a specific portion of the microlens from the measured value of the transmitted light, and a portion having a significant difference from the others, and determines the failure.

[0017]

Embodiments of the present invention will be described below with reference to the drawings. FIG. 1 is a principle diagram of the microlens inspection apparatus of the present invention.

The parallel light incident means 11 is a micro lens 1
2, the parallel light L2 is incident. The parallel light incident means 11
Is composed of a light source 11a and a lens system 11b. The lens system 11b converts the diffused light L1 from the light source 11a into a parallel light L2.

The inspection processing means 14 includes the micro lens 1
2. By taking in the transmitted light L3 transmitted through the slit 13,
From the measured value of the transmitted light L3, only a specific portion of the microlens 12 having a significant difference from the others is selected and determined to be defective.

The inspection processing means 14 includes a CCD 14a for capturing the transmitted light L3 or another alternative means, and an information processing apparatus 1 such as a personal computer for performing inspection processing of the captured image.
4b. Further, the slit 13 may not always be necessary, but in order to improve the measurement accuracy,
Alternatively, it is used to compensate for the lack of parallelism of incident light.

Next, the operation will be described with reference to FIG. FIG. 2 is a flowchart showing the operation procedure of the microlens inspection apparatus 10 of the present invention. [S1] The diffused light L1 emitted from the light source 11a becomes parallel light L2 while passing through the lens system 11b. [S2] The parallel light L2 is incident on the micro lens 12. Note that the micro lens 12 is movable with respect to the parallel light L2, but is basically positioned orthogonally. [S3] After passing through the microlens 12, the parallel light L2 passes through the slit 13 and passes through the CCD 1 of the inspection processing means 14.
Enter 4a. [S4] In the image captured by the CCD 14a, a measurement value of the transmitted light L3 is obtained by the information processing device 14b, and only a specific portion of the microlens 12 having a significant difference from the others is selected and determined to be defective. .

Next, the incident relationship of the parallel light L2 to the micro lens 12 will be described. FIG. 3 is a diagram in which the micro lens 12 is inclined with respect to the parallel light L2. The microlenses 12 are arranged orthogonal to the parallel light L2, or are inclined with respect to the parallel light L2 as shown in the figure.

As described above, the parallel light L2 is transmitted to the micro lens 1
2, and the light is incident by tilting the microlens 12 with respect to the parallel light L2 if necessary. However, the slit 13 is basically fixed.

As described above, the parallel light L
Light having regularity as shown in FIG. 2 is incident, and light passing through the microlens 12 is quantitatively measured. Then, the measured value of the transmitted light L3 is obtained by adjusting the inclination of the micro lens 12,
If only a specific portion has a significant difference than others, that portion is determined to be defective.

As described above, the microlens inspection apparatus 10 of the present invention uses transmitted light L3 instead of reflected light on the surface of the microlens 12. In addition, the transmitted light L3 is quantitatively measured using the incident light as the parallel light L2, and the presence or absence of a defect of the microlens 12 and the defective portion are specified based on the level.

[0026] As a result, the inspection can be performed quantitatively without relying on the visual inspection by a human, so that the inspection efficiency and accuracy can be improved. Next, the slit 13 will be described with reference to FIGS. FIG. 4 is a view showing a round slit. The slit 13a has a round portion 13 with a round shape.
Light passes through a-1.

FIG. 5 is a view showing a square matrix type slit. The slit 13b has a square matrix type and a rectangular portion 13b.
Light passes through -1. FIG. 6 is a view showing a delta type slit. The slit 13c is a delta-shaped square portion 13c.
Light passes through -1.

As described above, depending on the type of the microlens 12, the manner in which the microlens 12 is used, or the accuracy of the measurement, the optimum slit 13 including the above-mentioned or another shape is used.

Next, the transmitted light L3 will be described. FIG. 7 is a diagram illustrating a state of transmitted light L3 when light is incident on only one microlens 12 without using the slit 13.

As an inspection method, one of the microlenses 12
If light is sequentially incident on each individual part and the transmitted light L3 is measured, if the microlens 12 has a defect, the measured value changes (the measured value increases or decreases). It can be detected, inspected and sorted.

FIG. 8 is a diagram showing an example in which a square delta type slit is used for the slit 13. In this case, the parallel light L2 was incident on the entire microlens 12. Since the area around the opening of the slit 13 is shielded from light, if the microlens 12 condenses more light than usual due to an irregular shape or the like, even a slight difference can be clearly detected.

That is, the ordinary light-gathering level is gray, and only the portion where more light is gathered than usual due to the irregular shape of the microlens 12 looks very bright. By processing the transmitted light L3 by the information processing device 14b such as a personal computer, the inspection of the microlens 12 can be automatically and quantitatively and efficiently inspected and selected without omission, and a defective portion can be specified. It will also contribute to the improvement of the quality.

As described above, in the microlens inspection apparatus 10 of the present invention, the parallel light L
2, the transmitted light L3 is taken in, and the inspection processing means 14 determines a defective portion based on the measured value of the transmitted light L3.

As a result, since the inspection is not performed by human eyes, defect defects can be quantified, and the inspection accuracy and quality can be improved. In addition, since the inspection is not performed by human eyes, there is no inspection omission such as oversight,
Re-examination becomes unnecessary, and the inspection time can be shortened.

In addition, there is no health problem due to the mechanical inspection. Further, computer management becomes possible, and management costs in production management can be reduced. Furthermore, by specifying the defective portion, the feedback to the process becomes accurate, and the yield can be improved.

In the above description, the parallel light L2 is generated from the light source 11a using the lens system 11b, but a laser beam may be used as the parallel light. Also, the lens system 11
An optical jig such as a slit may be further arranged between b and the micro lens 12.

Further, although the slit 13 is fixed, the slit 13 and the CCD 14a may be three-dimensionally movable as required for inspection.

[0038]

As described above, according to the microlens inspection apparatus of the present invention, parallel light is made incident on the microlens, the transmitted light is taken in, and the defective portion is inspected by the inspection processing means based on the measured value of the transmitted light. It was configured to judge. As a result, the inspection can be performed quantitatively without relying on the visual inspection of a human, so that the inspection efficiency can be improved.

[Brief description of the drawings]

FIG. 1 is a principle diagram of a microlens inspection apparatus according to the present invention.

FIG. 2 is a flowchart showing an operation procedure of the microlens inspection apparatus of the present invention.

FIG. 3 is a diagram in which a micro lens is inclined with respect to parallel light.

FIG. 4 is a view showing a round slit.

FIG. 5 is a diagram showing a square matrix type slit.

FIG. 6 is a view showing a delta type slit.

FIG. 7 is a diagram showing a state of transmitted light when light is incident on only one microlens without using a slit.

FIG. 8 is a diagram showing an example in which a square delta type slit is used.

FIG. 9 is a diagram showing a cross section of a microlens substrate.

FIG. 10 is a schematic sectional view when a microlens substrate is used for an LCD.

FIG. 11 is a diagram showing microlens defects. (A)
FIG. 7B is a diagram showing a deformed microlens, FIG. 7B is a diagram showing the microlens not filled with resin, and FIG.

FIG. 12 is a view showing a conventional microlens inspection method.

[Explanation of symbols]

10 microlens inspection device, 11a light source, 1
1b: lens system, 12: micro lens, 13:
Slit, 14 ... inspection processing means, 14a ... CCD,
14b: information processing device, L1: diffused light, L2: parallel light, L3: transmitted light.

Claims (5)

[Claims] 1. A microlens inspection apparatus for improving inspection of microlens formation, comprising: a parallel light incident means for inputting parallel light to a microlens; and transmitting light transmitted through the microlens to obtain the transmitted light. Inspection processing means for determining a measured value of, and selecting only a specific portion of the microlens having a significant difference from the others from the measured value, and determining that the defective portion is defective. apparatus. 2. The microlens inspection apparatus according to claim 1, wherein the microlenses are arranged orthogonally to the parallel light or inclined with respect to the parallel light. 3. The microlens inspection apparatus according to claim 1, further comprising a slit between the microlens and the inspection processing means. 4. The microlens inspection apparatus according to claim 1, wherein said parallel light incident means comprises a light source and a lens system for converting diffused light from said light source into said parallel light. 5. The microlens inspection apparatus according to claim 1, wherein said parallel light incidence means enters laser light as said parallel light into said microlens.