JP2005114520A - Inspection apparatus and inspection method for electro-optical device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To accurately measure optical characteristics of an electro-optical device.
An inspection apparatus for inspecting the optical characteristics of an electro-optical device for projection display, in which an electro-optical material layer is sandwiched between a pair of substrates, and a light source means for irradiating light to the electro-optical device; A projection optical system including a capture diaphragm in which light emitted from the electro-optical device is incident on an opening that defines a light capture area, a projection lens that projects light captured through the capture diaphragm, and the projected light And a measurement unit that measures optical characteristics by detecting the.
[Selection] Figure 4

Description

  The present invention relates to a technical field of an inspection device for an electro-optical device such as a liquid crystal panel used as a light valve in a projection display device such as a liquid crystal projector.

  According to this type of inspection apparatus, the optical characteristics of the electro-optical device are measured by irradiating the electro-optical device with light emitted from the light source and detecting the emitted light from the electro-optical device using, for example, an illuminometer. (For example, refer to Patent Document 1). An actual projection display device includes a projection optical system that enlarges and projects a display image on the electro-optical device on a screen. In the inspection apparatus, an optical system similar to the projection optical system is provided on the light emission side with respect to the electro-optical apparatus. Then, the outgoing light from the electro-optical device is incident on the illuminometer through this outgoing side optical system.

JP 2002-365162 A

  It is desirable that the measurement value obtained by the measurement of the optical characteristic is correlated with the measurement value in the projection display device in which the electro-optical device is incorporated. However, in the emission side optical system, since the emission light from the electro-optical device is not controlled in the same manner as in the actual projection optical system, it becomes impossible to perform measurement correlated with the actual projection display device. . That is, there is a problem that the measurement accuracy of the optical characteristics is lowered.

  On the other hand, in order to measure or inspect such optical characteristics with high accuracy, it may be considered that the measurement or inspection is incorporated into an actual projector or the like. However, in this case, there is a technical problem that it is very difficult to obtain measurement results and inspection results under a uniform standard due to various factors such as aging and deterioration of the light source and variations in light quantity. Arise.

  The present invention has been made in view of the above problems, and it is an object of the present invention to provide an inspection apparatus for an electro-optical device that can accurately measure optical characteristics in the inspection of an electro-optical device such as a liquid crystal panel. And

  In order to solve the above-described problems, an electro-optical device inspection apparatus according to the present invention is an inspection device that inspects the optical characteristics of a projection-type display electro-optical device in which an electro-optical material layer is sandwiched between a pair of substrates. A light source means for irradiating light to the electro-optical device, and an opening for defining a light capturing area. The light is emitted from the electro-optical device due to light irradiated by the light source means. Measuring the optical characteristics by detecting the projected light, a capture optical system that includes a capture aperture that captures light through the aperture, a projection lens that projects the light captured by the capture aperture And a measuring unit.

  In the electro-optical device inspection apparatus according to the present invention, during operation, the light applied to the electro-optical device is emitted from the electro-optical material layer as transmitted light through the electro-optical material layer, for example. The light emitted from the electro-optical material layer is not limited to transmitted light. For example, when a reflective electro-optical device is used, the light is emitted as reflected light through the electro-optical material layer. In this way, the light emitted from the electro-optical device is captured by a capture aperture having an opening that defines a light capture region.

  Here, the “light capturing area” means a light incident area in the projection lens of the projection optical system provided in the next stage of the capturing stop on the optical path. That is, it means a region of light taken into the projection lens by the taking-in stop on a cross section perpendicular to the optical path of the light emitted from the electro-optical device. In an actual projection display device, in order to adjust the display position of the image on the screen, by changing the sectional shape of the projection lens and limiting the transmitted light from the electro-optical device, the emitted light of the projection lens May be adjusted.

  The intake diaphragm is configured by exchanging a variable diaphragm such as a diaphragm of a camera having a variable aperture diameter, or one or more types of aperture diameters. By using the capture aperture, the light capture area can be configured to correspond to the cross-sectional shape of the projection lens in the actual projection display device as described above. That is, in the inspection apparatus of the present invention, preferably, the opening diameter and the shape of the opening in the opening portion of the intake diaphragm are configured in consideration of the cross-sectional shape of the projection lens in the actual projection display device as described above. Therefore, according to the inspection apparatus of the present invention, it is possible to limit the emitted light from the electro-optical device, like the actual projection display device.

  In particular, due to the take-in stop, for example, near the periphery of the emitted light on the beam cross section of the emitted light from the electro-optical device that contains a relatively large amount of oblique light components due to misalignment between the pair of substrates. Can block the light part. On the other hand, in the case of a real machine, the oblique light component caused by such a misalignment is generally limited by the projection optical system such as an actual projector, so for example on the projection screen, the contrast ratio in the real machine There is almost no impact. Therefore, if a state similar to the actually projected state is constructed by inserting the capture aperture in the front stage of the projection lens as described above, the contrast ratio in the actual machine can be measured with high accuracy.

  As described above, the light taken into the projection lens through the opening of the taking-in stop is projected onto the measurement unit by the projection lens in the same manner as in an actual projection display device. At this time, in the electro-optical device, for example, all black display or all white display is performed as a display of a predetermined inspection pattern. Then, the transmitted light from the electro-optical device is emitted as display light and projected onto the measurement unit by the projection optical system. In addition, it is preferable that the projection optical system is provided with a diaphragm for limiting the light emitted from the projection lens with respect to the projection lens. If it does in this way, it will become possible to make light inject into a measuring part in the state nearer to an actual projection type display apparatus.

  The measurement unit includes, for example, an illuminance meter having a photodiode, a CCD (Charged Coupled Device), etc., and measures the illuminance of the detected light. The measurement unit calculates transmittance or contrast as an optical characteristic of the electro-optical device based on the measured illuminance. Alternatively, the measurement unit may represent the optical characteristics of the electro-optical device as a light distribution. The light distribution is represented as a distribution of illuminance, contrast, or transmittance.

  As a result of the above, according to the inspection apparatus of the present invention, it is possible to perform a measurement correlated with the measurement in the actual projection display apparatus for the optical characteristics of the same electro-optical apparatus. As a result, it is possible to perform highly accurate measurement on the optical characteristics of the electro-optical device. Furthermore, compared to a case where an electro-optical device is incorporated into an actual projector or the like to perform measurement or inspection, it is possible to output measurement results and inspection results under a uniform standard.

  In an aspect of the inspection apparatus for the electro-optical device according to the aspect of the invention, the projection lens is adjacent to the capture diaphragm without any other optical member on the optical path of the light captured by the capture diaphragm. Yes.

  According to this aspect, on the optical path, the taking-in diaphragm and the projection lens are arranged so as to contact or contact each other through a medium such as air without passing through other optical components. For this reason, as described above, it is possible to capture the light captured by the projection lens with high accuracy through the aperture of the capture aperture, and thus it is possible to perform highly accurate measurement of the optical characteristics of the electro-optical device. .

  In another aspect of the inspection apparatus for an electro-optical device according to the aspect of the invention, the light source unit includes a light source and a condensing unit that condenses the light emitted from the light source on the electro-optical device.

  According to this aspect, by using the condensing means, it is possible to efficiently irradiate the electro-optical device with the light emitted from the light source. In addition, it is preferable that an aperture is provided in the light collecting means, and the emitted light from the light collecting means is limited by the aperture. In this way, light can be incident on the electro-optical device in the same manner as in an actual projection display device.

  In another aspect of the inspection apparatus for an electro-optical device according to the present invention, the capture aperture is configured to be removable.

  According to this aspect, the misalignment can be detected by measuring the optical characteristics of the electro-optical device by removing or attaching the intake diaphragm. Here, in the manufacture of the electro-optical device, if a pair of substrates are misaligned and bonded together, a misalignment occurs. As the degree of misalignment increases, the light emitted from the electro-optical device includes a relatively large amount of light traveling in a direction different from the vertical direction with respect to the light output surface of the electro-optical device.

  Further, in an actual projection display device, the cross-sectional shape of the projection lens is configured so that a large amount of light traveling in the vertical direction is incident on the light exit surface of the electro-optical device out of the light emitted from the electro-optical device. Is done.

  Accordingly, when the optical characteristics of the electro-optical device whose degree of misalignment is outside the allowable range with the capture aperture removed, the correlation between the obtained measured value and the measured value in the actual projection display device is lowered. .

  When the taking-in diaphragm is attached, it is possible to limit the light emitted from the electro-optical device even in the case of an electro-optical device whose degree of misalignment is outside the allowable range, as in the case of an actual projection display device. That is, the projection lens in the projection optical system captures a large amount of light emitted from the electro-optical device in the vertical direction with respect to the light emission surface of the electro-optical device. Therefore, when the optical aperture of the electro-optical device is measured with the capture aperture attached and the degree of misalignment in the electro-optical device is within the allowable range or outside the allowable range, Correlation with a measured value in an actual projection display device is increased.

  Therefore, for the optical characteristics measured by the measuring unit, the misalignment in the electro-optical device is allowed by correlating the measured value with the capture aperture attached and the measured value with the capture aperture removed. It is possible to check whether it is within the range.

  In addition, as an optical characteristic of the electro-optical device, a viewing angle characteristic can be obtained based on a light distribution. Then, by comparing the viewing angle characteristics between when the capture aperture is attached and when the capture aperture is removed, it is possible to check whether the misalignment in the electro-optical device is within an allowable range.

  In another aspect of the inspection apparatus for an electro-optical device according to the present invention, the capture aperture is a plurality of apertures having different aperture diameters, and one of them can be selected and arranged with respect to the electro-optical device. It is configured.

  According to this aspect, even when a plurality of types of electro-optical devices are exchanged and optical characteristics are inspected, a plurality of apertures can be exchanged and used as the taking-in aperture according to the type of the electro-optical device. For example, according to the panel size and the outer shape of the image display area in the electro-optical device, by changing the aperture diameter or the shape of the aperture by exchanging a plurality of apertures, the optical characteristics of the electro-optical device can be measured with higher accuracy. It can be carried out.

  In another aspect of the inspection apparatus for an electro-optical device according to the present invention, the capture diaphragm is provided so as to be movable in a plane perpendicular to the optical path of the light emitted from the electro-optical device.

  According to this aspect, it is possible to perform measurement with higher accuracy with respect to the optical characteristics of the electro-optical device. In an actual projection display device, in order to adjust the display position of an image on the screen, the arrangement position of the projection lens may be changed by moving the projection lens with respect to the electro-optical device. Corresponding to the configuration of the projection lens arranged in this way, the pickup aperture is moved with respect to the electro-optical device and the arrangement position thereof is changed, so that the light from the electro-optical device to the projection optical system can be changed. The optical path can be adjusted, and light can be projected onto the measurement unit in the same manner as in an actual projection display device.

  The electro-optical device inspection method of the present invention is an inspection method for inspecting the optical characteristics of a projection-type display electro-optical device in which an electro-optical material layer is sandwiched between a pair of substrates. Then, the light irradiated on the electro-optical device and emitted through the electro-optical material layer is captured by a capture aperture having an opening that defines a light capture region, and the light captured by the capture aperture is projected to the projection lens. And the step of measuring the optical characteristics by detecting the projected light.

  In the inspection method for the electro-optical device according to the present invention, as with the inspection device according to the present invention described above, the optical characteristics of the electro-optical device can be measured with high accuracy.

  In one aspect of the inspection apparatus for an electro-optical device according to the present invention, in the step of measuring the optical characteristics, the optical characteristics are measured in a state in which the capture aperture is attached and in a state in which the capture aperture is removed.

  According to this aspect, the misalignment can be detected by measuring the optical characteristics of the electro-optical device by removing or attaching the intake diaphragm. In addition, as an optical characteristic of the electro-optical device, a viewing angle characteristic is obtained based on a light distribution. Then, by comparing the viewing angle characteristics between when the capture aperture is attached and when the capture aperture is removed, it is possible to check whether the misalignment in the electro-optical device is within an allowable range.

  Such an operation and other advantages of the present invention will become apparent from the embodiments described below.

  Hereinafter, embodiments of the present invention will be described with reference to the drawings. In this embodiment, the projection type liquid crystal device is inspected as a projection type electro-optical device.

<1: First Embodiment>
First, a first embodiment according to the inspection apparatus of the present invention will be described with reference to FIGS. 1 to 5.

<1-1: Configuration of Electro-Optical Device>
First, the configuration of the electro-optical device according to the present embodiment will be described with reference to FIGS. 1 and 2. FIG. 1 is a plan view of the electro-optical panel when the TFT array substrate is viewed from the side of the counter substrate together with each component formed thereon, and FIG. 2 is a cross-sectional view taken along line HH ′ of FIG. It is.

  Here, a TFT active matrix driving type liquid crystal device with a built-in driving circuit, which is an example of an electro-optical device, is taken as an example. This liquid crystal device is used as a light valve in a projection display device such as a liquid crystal projector.

  1 and 2, in the electro-optical device according to the present embodiment, a TFT array substrate 10 and a counter substrate 20 are disposed to face each other. A liquid crystal layer 50 is sealed between the TFT array substrate 10 and the counter substrate 20, and the TFT array substrate 10 and the counter substrate 20 are provided with a sealing material 52 provided in a seal region positioned around the image display region 10a. Are bonded to each other.

  The sealing material 52 is made of, for example, an ultraviolet curable resin, a thermosetting resin, or the like for bonding the two substrates, and is applied on the TFT array substrate 10 in the manufacturing process and then cured by ultraviolet irradiation, heating, or the like. It is. Further, in the sealing material 52, a gap material such as glass fiber or glass beads for dispersing the distance (inter-substrate gap) between the TFT array substrate 10 and the counter substrate 20 to a predetermined value is dispersed. That is, the electro-optical device according to the present embodiment is suitable for a small and enlarged display for a projector light valve.

  A light-shielding frame light-shielding film 53 that defines the frame area of the image display area 10a is provided on the counter substrate 20 side in parallel with the inside of the seal area where the sealing material 52 is disposed. However, part or all of the frame light shielding film 53 may be provided as a built-in light shielding film on the TFT array substrate 10 side.

  In the area extending around the image display area 10 a, the data line driving circuit 101 and the external circuit connection terminal 102 extend along one side of the TFT array substrate 10 in an area located outside the sealing area where the sealing material 52 is disposed. Is provided. The scanning line driving circuit 104 is provided along two sides adjacent to the one side so as to be covered with the frame light shielding film 53. Further, in order to connect the two scanning line driving circuits 104 provided on both sides of the image display area 10a in this way, the TFT array substrate 10 is covered with the frame light shielding film 53 along the remaining side. A plurality of wirings 105 are provided. In addition, a test terminal (not shown) to which a test drive signal described later is applied may be provided separately from the external circuit connection terminal 102.

  In addition, vertical conduction members 106 that function as vertical conduction terminals between the two substrates are disposed at the four corners of the counter substrate 20. On the other hand, the TFT array substrate 10 is provided with vertical conduction terminals in a region facing these corner portions. Thus, electrical conduction can be established between the TFT array substrate 10 and the counter substrate 20.

  In FIG. 2, on the TFT array substrate 10, an alignment film is formed on the pixel electrode 9a after the pixel switching TFT, the scanning line, the data line and the like are formed. On the other hand, on the counter substrate 20, in addition to the counter electrode 21, a lattice-shaped or striped light-shielding film 23 and an alignment film are formed on the uppermost layer portion. Further, the liquid crystal layer 50 is made of, for example, a liquid crystal in which one or several types of nematic liquid crystals are mixed, and takes a predetermined alignment state between the pair of alignment films. Further, a polarizing plate (not shown) corresponding to the orientation direction is provided on the back side of each facing surface of the TFT array substrate 10 and the counter substrate 20.

  In addition to the data line driving circuit 101, the scanning line driving circuit 104, and the like, the image signal on the image signal line is sampled and supplied to the data line on the TFT array substrate 10 shown in FIGS. Sampling circuit, precharge circuit for supplying a precharge signal of a predetermined voltage level to a plurality of data lines in advance of the image signal, for inspecting the quality, defects, etc. of the electro-optical device during production or at the time of shipment An inspection circuit or the like may be formed.

<1-2: Configuration in Pixel Unit>
Hereinafter, the configuration of the pixel portion of the electro-optical device according to the present embodiment will be described with reference to FIG. FIG. 3 is an equivalent circuit of various elements, wirings, and the like in a plurality of pixels formed in a matrix that forms the image display region 10a of the electro-optical device.

  In FIG. 3, each of a plurality of pixels formed in a matrix that forms the image display region 10a of the electro-optical device according to the present embodiment includes a pixel electrode 9a and a TFT 30 for switching control of the pixel electrode 9a. The data line 6 a formed and supplied with an image signal is electrically connected to the source of the TFT 30. The image signals S1, S2,..., Sn written to the data lines 6a may be supplied line-sequentially in this order, or may be supplied for each group to a plurality of adjacent data lines 6a. Good.

  Further, the gate electrode 3a is electrically connected to the gate of the TFT 30, and the scanning signals G1, G2,..., Gm are pulse-sequentially applied in this order to the scanning line 11a and the gate electrode 3a at a predetermined timing. It is comprised so that it may apply. The pixel electrode 9a is electrically connected to the drain of the TFT 30, and the image signal S1, S2,..., Sn supplied from the data line 6a is obtained by closing the switch of the TFT 30 as a switching element for a certain period. Write at a predetermined timing.

  Image signals S 1, S 2,..., Sn written in a liquid crystal as an example of an electro-optical material via the pixel electrode 9 a are held for a certain period with the counter electrode formed on the counter substrate. The liquid crystal modulates light and enables gradation display by changing the orientation and order of the molecular assembly depending on the applied voltage level. In the normally white mode, the transmittance for incident light is reduced according to the voltage applied in units of each pixel, and in the normally black mode, the light is incident according to the voltage applied in units of each pixel. The light transmittance is increased, and light having a contrast corresponding to the image signal is emitted from the electro-optical device as a whole.

  In order to prevent the image signal held here from leaking, a storage capacitor 70 is added in parallel with the liquid crystal capacitor formed between the pixel electrode 9a and the counter electrode. The storage capacitor 70 is provided side by side along the scanning line 11a, and includes a capacitor electrode 300 including a fixed potential side capacitor electrode and fixed at a constant potential.

  In FIG. 1, the scanning line driving circuit 104 supplies the scanning signals G1, G2,..., Gm to the scanning line 3a at a predetermined timing as described above (see FIG. 3), and the data line driving circuit 101 performs the image processing as described above. Signals S1, S2,..., Sn are supplied to the data line 6a at a predetermined timing (see FIG. 3).

<1-3: Configuration of inspection apparatus>
With reference to FIG. 4, the configuration of an inspection apparatus for inspecting the optical characteristics of the electro-optical apparatus configured as described above will be described. FIG. 4 schematically shows the configuration of the inspection apparatus on a cross section along the optical path.

  In FIG. 4, the inspection apparatus 400 includes a light source 42, an incident side optical system 43, a projection optical system 47 including a projection lens 406, an intake diaphragm 46, and a measurement unit 48 as main parts. The incident side optical system 43 corresponds to the “condensing means” according to the present invention, and the light source 42 and the incident side optical system 43 constitute the “light source means” according to the present invention. FIG. 4 shows a configuration in which each optical system has a common optical axis 40 in the inspection apparatus 400, but the optical axis of the projection optical system 47 is relatively set with respect to the optical axis of the incident side optical system 43. You may make it arrange | position by shifting.

  In FIG. 4, the light source 42 is configured as a fiber type, and the incident side optical system 43 can be irradiated with uniform and non-uniform light. The light source 42 may be configured using a laser device or a fluorescent tube.

  In the incident side optical system 43, a first lens 402a, a second lens 402b, and a third lens 402c are provided along the common optical axis 40 in order from the light incident side. A first diaphragm 404a is provided between the first lens 402a and the second lens 402b. A second diaphragm 404b is provided between the second lens 402b and the third lens 402c. The light emitted from the first lens 402a is limited by the first diaphragm 404a to adjust the light incident on the second lens 402b. In addition, the light emitted from the second lens 402b is limited by the second diaphragm 404b to adjust the light incident on the third lens 402c.

  A stage 401 is provided between the incident side optical system 43 and the projection optical system 47, and the electro-optical device 44 is held on the stage 401. The electro-optical device 44 is provided so that light is incident from the counter substrate 20 side via the stage 401 and transmitted light is emitted from the TFT array substrate 10 side. That is, the surface opposite to the side facing the liquid crystal layer 50 of the counter substrate 20 is held by the stage 401, and the surface opposite to the side facing the liquid crystal layer 50 of the TFT array substrate 10 is the surface of the electro-optical device 44. It becomes the light exit surface. In FIG. 4, the electro-optical device 44 is held horizontally on the stage 401 so that the optical axis 40 is perpendicular to the light exit surface. FIG. 4 shows a configuration in which the polarizing plates 45 a and 45 b are arranged in the optical path of the inspection apparatus 400 with respect to the electro-optical device 44.

  In FIG. 4, the light emitted from the third lens 402 c in the incident side optical system 43 is incident on the electro-optical device 44 via the polarizing plate 45 a and the stage 401. As described above, the light incident on the electro-optical device 44 can be adjusted by adjusting the light incident on the third lens 402c by the second diaphragm 404b.

  Furthermore, the stage 401 is configured to be slidable in the horizontal direction in the inspection apparatus 400 as indicated by an arrow A in FIG. The stage 401 is provided with a reference illuminance measurement opening 403. By sliding the stage 401, it is also possible to arrange the reference illuminance measurement opening 403 in the optical path instead of the polarizing plates 45a and 45b and the electro-optical device 44.

  The take-in stop 46 is provided so that light emitted from the electro-optical device 44 is incident through the polarizing plate 45b. The projection optical system 47 includes a projection lens 406 and a third diaphragm 404c. Light emitted from the electro-optical device 44 is incident on the projection lens 406 via the capturing aperture 46.

  The measurement unit 48 includes an illuminance meter 410 on which light emitted from the projection lens 406 enters through the third diaphragm 404c, and an inspection terminal 412 connected to the illuminance meter 410. The third diaphragm 404c limits the light emitted from the projection lens 406 and adjusts the light incident on the illuminometer 410. The inspection terminal 412 is configured by a personal computer, a workstation, or the like.

  The inspection apparatus 400 is preferably provided with inspection drive means (not shown) for supplying an inspection drive signal to the electro-optical device 44. The inspection drive unit includes, for example, a probe for applying an inspection drive signal to an external circuit connection terminal or an inspection terminal of the electro-optical device, and a connection part for applying via a flexible connector.

<1-4: Inspection of electro-optical device>
Next, with reference to FIG. 5 in addition to FIG. 4, the inspection of the optical characteristics of the electro-optical device 44 performed by the inspection device 400 will be described. 5A shows the measurement result of the transmittance as the optical characteristic of the electro-optical device 44, and FIG. 5B shows the measurement result of the contrast as the optical characteristic of the electro-optical device 44. is there.

  At the time of inspection, an inspection drive signal is output from the inspection drive means. In the electro-optical device 44, the scanning signals G1, G2,..., Gm and the image signals S1, S2, and the like output from the scanning line driving circuit 104 and the data line driving circuit 101 based on the supplied inspection driving signal. ..., Sn is supplied to each pixel portion, whereby a predetermined inspection pattern is displayed in the image display area 10a. In the present embodiment, in the image display area 10a, the display of the predetermined inspection pattern is preferably performed as all white display or all black display. If the electro-optical device is in a normally white mode, it is possible to inspect all white display in a state where no inspection drive signal is applied. If the electro-optical device is in a normally black mode, It is also possible to inspect all black display in a state where no inspection drive signal is applied.

  Here, in an actual projection display device, in order to adjust the display position of the image on the screen, the projection lens is limited by changing the cross-sectional shape of the projection lens and restricting the emitted light from the electro-optical device. May be adjusted.

  The light capturing area in the projection lens 406 is defined by the aperture diameter and the aperture shape of the capturing diaphragm 46 so as to correspond to the cross-sectional shape of the projection lens in the actual projection display device as described above. Therefore, it is possible to limit the light emitted from the electro-optical device 44 by the capturing aperture 46, as in the case of an actual projection display device.

  Further, according to the configuration of the inspection apparatus 400 shown in FIG. 4, the light is adjusted as described above by the first diaphragm 404a and the second diaphragm 404b provided in the incident side optical system 43, so that In the same manner as the projection display apparatus, the electro-optical device 44 can be irradiated with light. Further, by restricting the light emitted from the projection lens 406 by the third diaphragm 404c provided in the projection optical system 47, it is possible to make the light incident on the illuminometer 410 as in the case of an actual projection display device. It becomes.

  In the measurement unit 410, the illuminometer 410 measures the illuminance of the incident light. Then, the inspection terminal 412 calculates transmittance or contrast as the optical characteristic of the electro-optical device 44 based on the measured illuminance.

  Here, the transmittance is measured as follows. In the inspection apparatus 400, the stage 401 is slid to place the reference illuminance measurement opening 403 in the optical path. In this state, the light emitted from the third lens 402 c that has passed through the reference illuminance measurement opening 403 is incident on the projection lens 406 via the intake diaphragm 46. Therefore, the illuminance meter 410 measures the illuminance of light emitted from the projection lens 406 in a state where the polarizing plates 45a and 45b and the electro-optical device 44 are not disposed in the optical path. The illuminance measured in this way is set as the reference illuminance.

  On the other hand, the illuminance meter 410 measures the illuminance of light emitted from the projection lens 406 in a state where the polarizing plates 45a and 45b and the electro-optical device 44 are arranged in the optical path.

  The inspection terminal 412 calculates, as the transmittance, a ratio between the reference illuminance and the illuminance measured in a state where the polarizing plates 45a and 45b and the electro-optical device 44 are arranged in the optical path. FIG. 5A shows a graph showing the correlation between the transmittance calculated in this way and the transmittance measured in the same manner using the same electro-optical device 44 in the actual projection display device. is there. In FIG. 5A, the horizontal axis represents the measured value of the transmittance in the actual projection display device, and is shown as “measured value of the actual projector”, and the vertical axis represents the transmittance of the inspection device 400. The measured value is taken and indicated as “measured value of inspection device”.

  In FIG. 5 (a), the measured values of transmittance in an actual projection display device and the measured values of transmittance in the inspection device 400 corresponding to each of these measured values are proportional to each other and their correlation values. Becomes approximately 0.98.

  Next, contrast measurement will be described. In the inspection apparatus 400, the electro-optical device 44 performs all white display and all black display as display of a predetermined inspection pattern. The illuminance meter 410 measures the illuminance of light emitted from the projection lens 406 in all white display and all black display. The inspection terminal 412 calculates the ratio between the illuminance measured in the all white display and the illuminance measured in the all black display as the contrast.

  FIG. 5B shows a graph showing the correlation between the contrast calculated in this way and the contrast similarly measured using the same electro-optical device 44 in the actual projection display device. In FIG. 5B, the horizontal axis indicates the measured value of the contrast in the actual projection type display device, which is shown as “measured value of the actual projector”, and the vertical axis indicates the measured value of the contrast in the inspection device 400. And is shown as “measurement value of inspection apparatus”.

  In FIG. 5B, the measured contrast value in the actual projection display device and the measured contrast value in the inspection apparatus 400 corresponding to each of these measured values are proportional to each other, and the correlation value is almost equal. 0.96.

  As described above, according to the inspection device 400, the optical characteristics of the same electro-optical device can be measured in correlation with the measurement in the actual projection display device. As a result, it is possible to perform highly accurate measurement on the optical characteristics of the electro-optical device.

<2: Second Embodiment>
Next, a second embodiment according to the inspection apparatus of the present invention will be described. The inspection apparatus according to the second embodiment differs from the first embodiment in the configuration of the intake diaphragm. Therefore, in the following, the configuration of the inspection apparatus will be described with reference to FIG. 4, and the configuration of the intake diaphragm will be described with reference to FIG. The operation of the inspection apparatus will be described with reference to FIGS. In addition, the same code | symbol is attached | subjected and shown to a common part with 1st Embodiment, and the overlapping description is abbreviate | omitted below.

  First, the configuration of the intake stop 46 of the inspection apparatus 400 shown in FIG. 4 in the second embodiment will be described with reference to FIG. FIG. 6 is a perspective view schematically showing a configuration example of the intake diaphragm 46.

  In the second embodiment, in the inspection apparatus 400, the intake diaphragm 46 is configured to be removable as follows, for example. In FIG. 6, the intake stop 46 is installed in the optical path of the inspection apparatus 400 while being held by the holding plate member 602. The holding plate member 602 is provided with an opening 602 a having a shape corresponding to the outer shape of the intake diaphragm 46. The holding plate member 602 is configured to be attached by fitting the intake diaphragm 46 into the opening 602a or to be removable from the opening 602a.

  Next, with respect to the electro-optical device in which the measurement results shown in FIGS. 5A and 5B are obtained, the transmittance and contrast of the electro-optical device are measured in the same manner as in the first embodiment with the capturing aperture 46 removed. The measurement results obtained by performing the measurement will be described with reference to FIGS. 7 (a) and 7 (b). FIG. 7A is a diagram showing the same graph as FIG. 5A with respect to the transmittance value measured by the inspection apparatus 400 with the intake diaphragm 46 removed, and FIG. It is a figure which shows the graph similar to FIG.5 (b) about the value of the contrast measured in the test | inspection apparatus 400. FIG.

  In FIG. 7A, the measured values of transmittance in an actual projection display device and the measured values of transmittance in the inspection device 400 corresponding to each of these measured values are proportional to each other as in FIG. However, the correlation value decreases from about 0.98 to about 0.89.

  In FIG. 7B, the measured contrast value in the actual projection display device and the measured contrast value in the inspection device 400 corresponding to each of these measured values are proportional to each other as in FIG. However, the correlation value decreases from about 0.96 to about 0.45.

  In this way, the correlation value between the measured values of contrast and transmittance in the inspection device 400 and the measured values of contrast and transmittance in the actual projection display device with the capture aperture 46 removed is lowered. The reason is as follows.

  As the degree of misalignment in the electro-optical device increases, the outgoing light from the electro-optical device includes more light that travels in a direction different from the vertical direction with respect to the light output surface of the electro-optical device.

  Further, in an actual projection display device, the cross-sectional shape of the projection lens is configured so that a large amount of light traveling in the vertical direction is incident on the light exit surface of the electro-optical device out of the light emitted from the electro-optical device. Is done.

  Therefore, when the contrast or transmittance is measured with the capture aperture 46 removed, the greater the degree of misalignment in the electro-optical device, the lower the correlation between the obtained measured value and the measured value in the actual projection display device. Become.

  On the other hand, when the taking-in stop 46 is attached, it is possible to limit the light emitted from the electro-optical device, even in an electro-optical device whose degree of misalignment is outside the allowable range, as in an actual projection display device. . That is, the projection lens 406 in the projection optical system 47 receives a large amount of light emitted from the electro-optical device 44 in the vertical direction with respect to the light exit surface of the electro-optical device 44. Therefore, when the contrast or transmittance of the electro-optical device whose degree of misalignment is outside the allowable range with the capture aperture 46 attached is measured, the correlation between the obtained measurement value and the measurement value in the actual projection display device. Becomes higher.

  Therefore, in the inspection apparatus 400, whether the misalignment in the electro-optical device is within an allowable range by correlating the measured value with the capturing aperture 46 attached and the measured value with the capturing aperture 46 removed. It becomes possible to investigate whether or not. For example, the difference between the correlation coefficient in the graph shown in FIG. 5A and the correlation coefficient in the graph shown in FIG. 7A or the correlation coefficient in the graph shown in FIG. If the difference from the correlation coefficient in the graph shown in FIG. 7B is relatively small, it can be determined that the degree of misalignment in the electro-optical device to be inspected at this time is relatively small. Conversely, if this difference is relatively large, it can be determined that the degree of misalignment in the electro-optical device that is the object of inspection at this time is relatively large. Therefore, for example, if a threshold value is set in advance for the difference in correlation coefficient corresponding to the degree of misalignment that falls within the allowable range, whether or not the difference in correlation coefficient obtained as an inspection result has exceeded this threshold value. Thus, it is possible to easily determine whether or not the degree of misalignment is within the allowable range.

  In the inspection apparatus 400, the inspection terminal 412 may indicate the optical characteristics of the electro-optical device as a light distribution represented by the measured illuminance or the calculated contrast distribution. Furthermore, it is desirable that the inspection terminal 412 generate output data indicating viewing angle characteristics based on the light distribution.

  FIG. 8 is a schematic diagram for explaining the elevation angle θ and the azimuth angle φ that define the viewing angle. In FIG. 8, when the light exit surface of the electro-optical device 44 is a measurement surface and one point on the measurement surface is a measurement point 800, the azimuth angle φ is defined as a 0 ° position on the measurement surface. The left (L) 90 ° position, 180 ° position, and right (R) 90 ° position are defined clockwise from the 0 ° position. The elevation angle θ is θ = 0 ° when the observation point on the measurement surface is located directly above the measurement point 800, that is, on the normal line of the measurement surface, and the observation point is centered on the measurement point 800. When tilted on a concentric circle, the line connecting the observation point and the measurement point 800 represents the angle formed with respect to the normal of the measurement surface.

  The viewing angle characteristic is expressed, for example, by plotting the contrast value against the elevation angle θ. Therefore, by examining whether or not the elevation angle θ corresponding to the maximum contrast value in the viewing angle characteristic is different between when the capture aperture 46 is attached and when the capture aperture 46 is removed, the assembly in the electro-optical device is performed. It is possible to check whether or not the deviation is within an allowable range.

<3: Modification>
A modification of the first and second embodiments described above will be described. In the inspection apparatus 400 illustrated in FIG. 4, the intake diaphragm 46 may be configured to be a plurality of diaphragms having different opening diameters, and one of them may be selected and arranged with respect to the electro-optical device 44.

  The intake diaphragm 46 is configured as described with reference to FIG. Then, a plurality of apertures having different opening diameters are exchanged and attached to the opening 602a of the holding plate member 602. According to this configuration, in the inspection apparatus 400, when a plurality of types of electro-optical devices are replaced and the optical characteristics are inspected, the plurality of apertures are replaced and used as the intake stop 46 according to the type of the electro-optical device. It becomes possible. As a result, more accurate measurement can be performed on the optical characteristics of the electro-optical device.

  Further, it is preferable that the taking-in stop 46 is provided in the optical path of the inspection apparatus 400 so as to be movable in the direction along the substrate surface with respect to the electro-optical device 44.

  Here, in an actual projection type display device, in order to adjust the display position of the image on the screen, the arrangement position of the projection lens may be changed by moving the projection lens with respect to the electro-optical device. Corresponding to the configuration of the projection lens arranged in this way, the take-in stop 46 is moved with respect to the electro-optical device 44 to change its arrangement position, so that the electro-optical device 44 projects the projection optical system 47. It is possible to adjust the optical path of the light reaching to, and to project light onto the illuminometer 410 as in the case of an actual projection display device.

  The present invention is not limited to the above-described embodiments, and can be appropriately changed without departing from the spirit or idea of the invention that can be read from the claims and the entire specification, and an electro-optical device with such a change. These inspection apparatuses and inspection methods are also included in the technical scope of the present invention.

It is a top view which shows the whole structure of an electro-optical panel. It is H-H 'sectional drawing of FIG. 4 is an equivalent circuit of various elements, wirings, and the like in a plurality of pixel portions formed in a matrix that forms an image display region of an electro-optical panel. It is a figure showing the composition of an inspection device roughly. FIG. 5A is a diagram showing the measurement result of the transmittance, and FIG. 5B is a diagram showing the measurement result of the contrast. FIG. 6 is a perspective view schematically showing a configuration example of the intake diaphragm. FIG. 7A is a diagram showing the measurement result of transmittance, and FIG. 7B is a diagram showing the measurement result of contrast. It is a schematic diagram for demonstrating the elevation angle and azimuth which define a viewing angle.

Explanation of symbols

DESCRIPTION OF SYMBOLS 42 ... Light source 43 ... Incident side optical system 44 ... Electro-optical device 46 ... Capture stop 47 ... Projection optical system 48 ... Measurement part 400 ... Inspection apparatus 406 ... Projection lens

Claims (8)

An inspection apparatus for inspecting the optical characteristics of an electro-optical device for projection display, in which an electro-optical material layer is sandwiched between a pair of substrates,
Light source means for irradiating the electro-optical device with light;
An aperture that defines a light capture area, and a capture aperture that captures light emitted from the electro-optical device due to light emitted by the light source means through the aperture;
A projection optical system including a projection lens that projects light captured by the capture aperture;
An inspection apparatus for an electro-optical device, comprising: a measurement unit that measures the optical characteristics by detecting the projected light.   2. The electro-optical device according to claim 1, wherein the projection lens is adjacent to the capturing aperture without any other optical member on an optical path of light captured by the capturing aperture. Inspection equipment. The electro-optical device inspection apparatus according to claim 1, wherein the light source unit includes a light source and a condensing unit that condenses the light emitted from the light source onto the electro-optical device. The inspection apparatus for an electro-optical device according to any one of claims 1 to 3, wherein the intake diaphragm is configured to be removable. 5. The intake diaphragm is a plurality of diaphragms having different aperture diameters, one of which is selected and configured to be arranged with respect to the electro-optical device. The inspection apparatus for an electro-optical device according to claim 1. The electro-optical device according to claim 1, wherein the taking-in stop is provided so as to be movable in a plane perpendicular to an optical path of light emitted from the electro-optical device. Inspection equipment. An inspection method for inspecting the optical characteristics of an electro-optical device for projection display in which an electro-optical material layer is sandwiched between a pair of substrates,
Light emitted to the electro-optical device and emitted through the electro-optical material layer is captured by a capture aperture having an opening that defines a light capture region, and the light captured by the capture aperture is projected by a projection lens. And a process of
And a step of measuring the optical characteristic by detecting the projected light. An inspection method for an electro-optical device. The method for inspecting an electro-optical device according to claim 7, wherein in the step of measuring the optical characteristic, the optical characteristic is measured in a state in which the capturing aperture is attached and in a state in which the capturing aperture is removed.

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