Display optimization for night vision enhancement systems

• US 5,781,243 A
• Filed: 05/08/1995
• Issued: 07/14/1998
• Est. Priority Date: 05/08/1995
• Status: Expired due to Term

• Current Assignee: L-3 Communications Corporation (L3Harris Technologies, Inc.)
• Original Assignee: Hughes Electronics Corporation (Rtx Corporation)
• Inventors: Kormos, Alex L.
• Primary Examiner(s): Peng, John K.
• Assistant Examiner(s): Lo, Linus H.
• Application Number:
  US08/438,135
• Time in Patent Office: 1,163 Days
• Field of Search: 348/556, 348/39, 348/135, 348/136, 348/137, 348/140, 348/141, 348/169, 348/170, 348/164, 348/168, 348/36, 348/113, 348/148, 348/581, 348/704
• US Class Current: 348/556
• CPC Class Codes: G02B 2027/0138 comprising image capture systems, e.g. camera
• CPC Class Codes: G02B 23/12 with means for image conversion or intensification
• CPC Class Codes: G02B 27/0101 characterised by optical features G02B27/0172 takes precedence

Abstract

Night vision apparatus including an infrared night vision sensor having a selected field of view and a display panel positioned for displaying an image detected by the sensor, the display panel having a display aspect ratio optimized based upon the horizontal dimension of the field of view of the infrared sensor such that the display aspect ratio decreases as the horizontal field of view narrows.

Claims

1. A method of optimizing the scene presented to a viewer by a system employing a sensor including a wide angle optical system and a visual display comprising the steps of:

arranging said sensor to have a field of view of a selected horizontal dimension; and

selecting a physical ratio for said display based on said horizontal dimension.

2. The method of claim 1 wherein said sensor is mounted above a windshield and said display aspect ratio is selected according to a relationship whereby said display aspect ratio decreases as said horizontal dimension narrows so as to provide only as much information as a viewer sees out of the windshield with the naked eye.

3. The method of claim 2 further including the step of selecting the vertical field of view of said sensor to be 9 degrees.

4. The method of claim 3 further including the step of selecting the horizontal field of view of said sensor to be 27 degrees.

5. The method of claim 4 further including the step of selecting the mean distance from the display to the viewer'"'"'s eye to be 30 inches, the system image magnification to be 0.5:

1, and the display aspect ratio to be 3;

1.

6. The method of claim 2 further including the step of selecting the physical aspect ratio of the display (horizontal to vertical)

based upon the horizontal field of view (HFOV) such that,

if the HFOV is 58 degrees, the display aspect ratio is 5:

2;

if the HFOV is 33 degrees, the display aspect ratio is 4;

2;

if the HFOV is 27 degrees, the display aspect ratio is 5;

3; and

if the HFOV is 16 degrees, the display aspect ratio is 4;

3.

7. Apparatus comprising:

a night vision sensor having a selected horizontal and vertical field of view; and

a display means positioned for displaying an image to a viewer, the image being detected by said sensor, said display means having a length and width and a display physical ratio optimized based upon the horizontal dimension of said field of view.

8. The apparatus of claim 7 wherein the vertical field of view of said sensor is 9 degrees.

9. The apparatus of claim 8 wherein the horizontal field of view of said sensor is 27 degrees.

10. The apparatus of claim 9 wherein the mean distance from the display to the viewer'"'"'s eye is 30 inches, the image magnification is 0.5:

1, and said display aspect ratio is 3;

1.

11. The apparatus of claim 7 wherein the physical aspect ratio (horizontal to vertical) of the display is selected

based upon the horizontal field of view (HFOV) such that,

if the HFOV is 58 degrees, the display aspect ratio is 5:

2;

if the HFOV is 33 degrees, the display aspect ratio is 4;

2;

if the HFOV is 27 degrees, the display aspect ratio is 5;

3; and

if the HFOV is 16 degrees, the display aspect ratio is 4;

3.

12. The apparatus of claim 7 wherein said sensor is an infrared sensor.

13. A method of determining optimum physical horizontal and vertical dimensions of a display for use with a vision system, the vision system including a sensor having a predetermined horizontal field of view, the method comprising the step of:

determining a ratio of a horizontal and a vertical dimension of said display based upon the predetermined horizontal field of view of the sensor, wherein the ratio is determined according to a relationship whereby the wider the predetermined horizontal field of view of the sensor, the narrower the display'"'"'s physical vertical dimension.