JP3104752B2 - Screen inspection device - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a screen inspection apparatus for measuring the luminance and chromaticity of a color screen such as an LCD and a CRT.

[0002]

2. Description of the Related Art FIG. 2 shows a screen inspection apparatus conventionally used for measuring the luminance and chromaticity state of a color screen such as a CRT.

[0003] Conventional screen inspection devices include R, G, B (red,
Green, blue) filters 1, 2, 3, R, G, B photodiodes 4, 5, 6 and R, G, B photoamplifiers 7, 8, 9 , Provided inside the cylindrical sensor body 10. In the sensor main body 10, a G filter 2, a photodiode 5, and a photoamplifier 8 are sequentially arranged. And, on one side, R
A filter 3, a photodiode 4, and a photoamplifier 7 are sequentially arranged, and a filter 3 for B, a photodiode 6, and a photoamplifier 9 are sequentially arranged on the other side.

A color screen such as a CRT (CR in the case of example)
The light emitted from T) 11 passes through the R, G, B filters 1, 2, 3 and enters the R, G, B photodiodes 4, 5, 6 respectively. Each photodiode 4, 5, 6
Converts the received light amount into a current and sends it to each of R, G, and B photoamplifiers 7, 8, and 9. Each photo amplifier 7, 8, 9
Converts the current sent from each of the photodiodes 4, 5, and 6 into a voltage and outputs the voltage to an external signal processing unit 12. The signal processing unit 12 checks the white balance (R / G, B / G) based on the voltage signals sent from the photo amplifiers 7, 8, and 9, and measures the luminance and chromaticity state of the color screen 11 and the like. I do.

[0005]

However, the above-described conventional screen inspection apparatus is a system in which light emitted from the color screen 11 is directly received by the photodiodes 4, 5, and 6 for RGB.

(1) In order to prevent external light from entering the sensor body 10, the measurement must be performed with the tip of the sensor body 10 in close contact with the color screen 11 as shown in the figure.

(2) When the measurement range of the color screen 11 is limited by the cross-sectional area of the sensor main body 10 and the measurement range cannot be further increased, and it is necessary to search a wide range of the color screen 11 , Multiple measurements must be taken.

(3) In the case of an LCD display panel which generates a large amount of light in directions other than the direction perpendicular to the screen, the luminance and the like should be measured only from the light perpendicular to the screen. To detect the light emitted to
The measurement performance tends to be inferior to the case of RT. There was a problem.

Therefore, the present invention has been made in view of the above-mentioned circumstances, and it is not necessary to perform measurement by bringing a sensor body into close contact with a color screen, and a screen capable of freely setting a measurement range of a color screen. It is an object to provide an inspection device.

[0010]

SUMMARY OF THE INVENTION A screen inspection apparatus according to the present invention receives light emitted from a color screen through R, G, and B filters and converts the amount of light into a current.
B, each of the photodiodes for R, G, and B for converting a current sent from each of the photodiodes into a voltage and outputting the voltage to an external signal processing unit. In a screen inspection apparatus for measuring a degree state and the like, a lens system and a spectral prism are provided, and light emitted from a color screen is made incident on each photodiode via these.

[0011]

According to the above arrangement, the light emitted from the color screen enters the lens system, passes through the spectral prism, and the R, G, B filters, and enters the R, G, B photodiodes. . Accordingly, each of the R, G, and B photodiodes receives light emitted from the color screen via the lens system and the spectral prism.

Thus, the light emitted from the color screen can be received without entering external light even from a place distant from the color screen. Further, the measurement range of the color screen can be set freely according to the distance from the color screen and the magnification of the lens system.

[0013]

An embodiment of the present invention will be described below with reference to the drawings.

FIG. 1 shows a screen inspection apparatus according to the present invention.
This screen inspection device includes a sensor body 13 and a lens system 14.
, A spectral prism 15, and each filter 1 for R, G, B
6, 17, 18; R, G, and B photodiodes 19, 20, and 21, and R, G, and B photoamplifiers 2
2, 23, 24.

The lens system 14 is an interchangeable lens having a predetermined magnification that can be attached to and detached from the sensor body 13, and is mounted on a mount 25 provided at the center of one side (front side) of the sensor body 13 by, for example, a screw mount. Method (this embodiment)
And so on.

The spectral prism 15 is mounted at a position corresponding to the mount 25 in the sensor body 13.
The surface 26 from which the transmitted light of the spectral prism 15 is emitted
, A filter 17 for R is attached to one surface 27 from which refracted light is emitted, and a filter 16 for R is attached to
The filter 18 for B is attached to the other surface 28 from which the refracted light is emitted.

The R photodiode 19 and the photoamplifier 22 are sequentially arranged at positions corresponding to the R filter 16, and the G photodiode 20 and the photoamplifier 23 are sequentially arranged at positions corresponding to the G filter 17. The photodiode 21 for B and the photoamplifier 24 are sequentially arranged at positions corresponding to the filter 18 for B.

Photo amplifiers 22 and 2 for R, G and B
Reference numerals 3 and 24 are electrically connected to an external signal processing unit 29.

In the case of this screen inspection apparatus, light emitted from a color screen 30 such as a CRT or an LCD display panel is transmitted through the lens system 1.
4 is incident. The light that has entered the lens system 14 passes through the spectral prism 15 and the R, G, and B filters 16, 17, and 18, and then enters the R, G, and B photodiodes 19, 20, and 21, respectively. .

Each of the photodiodes 19, 20, and 21 converts the amount of light received into a current to convert the received light into a corresponding one of the photoamplifiers 22 and 2.
Send to 3,24. Each of the photoamplifiers 22, 23, and 24 converts the current sent from each of the photodiodes 19, 20, and 21 into a voltage and sends the voltage to the signal processing unit 29. Signal processing unit 29
Calculates the output of each of the photodiodes 19, 20, and 21 (for example, calculates R / G, B / G), and detects the luminance, chromaticity state, and the like.

In this embodiment, an interchangeable lens having a predetermined magnification is used as the lens system 14, but in this case, it is possible to cope with the size of the screen by replacing the interchangeable lens with a different magnification. . Further, a lens system 14 having a zoom function may be used.

[0022]

As described above, the screen inspection apparatus of the present invention is provided with the lens system and the spectral prism, and the light emitted from the color screen is incident on each of the R, G, B photodiodes via these. As a result, the luminance and chromaticity state of the color screen can be measured at a position away from the color screen. Therefore, even when measuring the LCD display panel, it is possible to receive only the light output in the direction perpendicular to the screen, and accurate measurement is possible. Also,
The measurement range can be freely set depending on the distance from the color screen and the magnification of the lens system, and even when measuring a wide range of the color screen, the measurement can be performed at one time.

[Brief description of the drawings]

FIG. 1 is a vertical sectional side view of a screen inspection apparatus according to one embodiment of the present invention.

FIG. 2 is a longitudinal sectional view of a conventional screen inspection device.

[Explanation of symbols]

 Reference Signs List 14 lens system 15 spectral prism 16 filter for R 17 filter for G 18 filter for B 19 photodiode for R 20 photodiode for G 21 photodiode for B 22 photo amplifier for R 23 photo amplifier for G 24 photo amplifier for B 29 signal Processing unit 30 Color screen

Claims (1)

(57) [Claims] A light emitted from a color screen is received through R, G, and B filters, and the R, G, and B photodiodes for converting the amount of light into a current and transmitted from each of the photodiodes. In a screen inspection apparatus including R, G, and B photoamplifiers for converting a supplied current into a voltage and outputting the voltage to an external signal processing unit, the luminance and chromaticity state of the color screen are measured. And a spectral prism, and light emitted from the color screen is incident on each of the photodiodes via the spectral prism.