Method and system for testing the performance of at least one electro-optical test device

• US 5,699,440 A
• Filed: 12/01/1994
• Issued: 12/16/1997
• Est. Priority Date: 12/02/1993
• Status: Expired due to Fees

• Current Assignee: Genop Limited
• Original Assignee: Genop Limited
• Inventors: Carmeli, Ran
• Primary Examiner(s): Bost, Dwayne
• Assistant Examiner(s): Johnson, Brian
• Application Number:
  US08/352,165
• Time in Patent Office: 1,111 Days
• Field of Search: 356/124, 356/124.5, 348/175, 348/176, 348/180, 348/184, 348/187, 348/188, 348/189, 348/190, 382/100, 382/141, 382/275, 364/551.01, 359/249, 359/307
• US Class Current: 382/100
• CPC Class Codes: H04N 17/002 for television cameras

Abstract

A method and system for testing the performance of at least one electro-optical test device, comprising constructing an electro-optical system having a light source, a test target, a lens and an imaging device as required in combination with the test devices. A respective identity code of a plurality of precalibrated devices together with corresponding electro-optical performances are stored in a database and the imaging device is aligned to the test target so as to produce a focused image thereof. Pre-calibbrated devices are selected from the database and the focussed image is digitized and stored so as to produce a digitized image which is analyzed so as to determine an electro-optical performance representative of the performance of the electro-optical system which is equal to the product of component electro-optical performances of each of the electro-optical test devices and each of the additional pre-calibrated devices. This permits determination of the product of component electro-optical performances of each of the electro-optical test devices.

Claims

1. A method for testing the performance of at least one electro-optical test device, comprising the steps of:

(a) selecting a plurality of electro-optical devices including a light source, a test target, a lens and an imaging means to construct an electro-optical system which consists of the plurality of electro-optical devices;

(b) selecting at least one electro-optical device of the electro-optical system to be an electro-optical test device;

(c) defining all the other electro-optical devices of the electro-optical system that have not been selected as electro-optical test devices as pro-calibrated devices of the system;

(d) creating a database for storing a respective identity code of a plurality of different types of pro-calibrated devices including said pre-calibrated devices of the system together with corresponding electro-optical performances,

(e) aligning the imaging means to the test target so as to produce a focused image thereof,

(f) digitizing and storing the focussed image so as to produce a digitized image,

(g) analyzing the digitized image so as to determine an electro-optical performance representative of the performance of the electro-optical system and being equal to the product of component electro-optical performances of each of said at least one electro-optical test device and each of said pre-calibbrated devices,

(h) accessing the database in order to extract the electro-optical performances of each of the electro-optical devices in the electro-optical system, and

(i) determining the product of component electro-optical performances of each of said at least one electro-optical test device.

2. The method according to claim 1, wherein:

said at least one electro-optical test device is selected from a group comprising light source, lens, target, camera, and

the target includes at least one test area constructed to permit measurement of said electro-optical performance.

3. The method according to claim 1, wherein:

said at least one electro-optical test device is a display device, and

the light source and target are an electronically generated test signal constructed to permit measurement of said electro-optical performance.

4. The method according to claim 1, wherein said electro-optical performance is representative of:

(a) Modular Transfer Function,

(b) Contrast Transfer Function,

(c) Grey Level Linearity,

(d) Illumination Uniformity,

(e) Geometrical Distortion,

(f) Signal to Noise Ratio,

(g) Transient Response,

(h) Blemishes,

(i) Blooming, and

(j) Chromaticity.

5. A system for testing the performance of at least one electro-optical test device, the system comprising:

an electro-optical system including said at least one electro-optical test device coupled to pre-calibrated devices, said electro-optical system comprising a light source, a target, a lens and an imaging means,

a computer coupled to the electro-optical system and including a memory for storing therein a database of pre-calibrated device identity codes and corresponding electro-optical performances thereof in respect of a plurality of different types of pre-calibrated electro-optical device including said pre-calibrated devices,

optical alignment means coupled to the electro-optical system and to the computer for permitting alignment of the electro-optical system and producing an indication signal when the electro-optical system is correctly aligned,

a setup means for specifying the identity codes of each of the pre-calibbrated devices in said electro-optical system,

a digitizing means coupled to the electro-optical system for digitizing an image produced by the electro-optical system and being coupled to said memory for storing therein a corresponding digitized image,

an analysis means coupled to the memory for determining an electro-optical performance representative of the performance of the electro-optical system and being equal to the product of component electro-optical performances of each of said at least one electro-optical test device and each of said pre-calibrated devices, said analysis means further for extracting from the database the electro-optical performances of each of the pre-calibrated devices and for determining the product of component electro-optical performances of each of said at least one electro-optical test device.

6. The system according to claim 5, wherein:

said at least one electro-optical test device is selected from a group comprising light source, lens, target, camera, and

the target includes at least one test area constructed to permit measurement of said electro-optical performance.

7. The system according to claim 5, wherein:

said at least one electro-optical test device is a display device, and

the light source and target are an electronically generated test signal constructed to permit measurement of said electro-optical performance.

8. The system according to claim 5, wherein said electro-optical performance is representative of:

(a) Modular Transfer Function,

(b) Contrast Transfer Function,

(c) Grey Level Linearity,

(d) Illumination Uniformity,

(e) Geometrical Distortion,

(f) Signal to Noise Ratio,

(g) Transient Response,

(h) Blemishes,

(i) Blooming, and

(j) Chromaticity.

9. The system according to claim 6, wherein:

the target includes a high accuracy pre-calibrated reticle for forming an image by said at least one electro-optical test device, and

the analysis unit analyzes said image so as to determine the combined optical performance of the at least one test device.

10. The system according to claim 9, wherein the reticle is provided with at least two discrete patterns thereon each for producing respective test images whereby corresponding functions of the electro-optical device can be tested simultaneously.

11. The system according to claim 9, wherein the reticle is provided with a shaping edge pattern for determining the Modular Transfer Function of the electro-optical device.

12. The system according to claim 9, wherein each pattern on the reticle is repeated in different areas of the reticle in order to permit spatial variation in the performance of the optical component to be determined.

13. For use in the system according to claim 5, a high accuracy pre-calibbrated reticle for forming an image of at least one test pattern by an optical device whose optical performance is to be determined.

14. The reticle according to claim 13, wherein there are provided thereon at least two discrete test patterns each for producing respective test images, whereby corresponding functions of the optical components can be tested simultaneously.

15. The reticle according to claim 13, wherein there is provided a shaping edge pattern for determining the Modular Transfer Function of the optical component.

16. The reticle according to claim 13, wherein each said at least one test pattern is repeated in different areas of the reticle in order to permit spatial variation in the performance of the optical component to be determined.