Sensor for dual wavelength bands

• US 7,075,079 B2
• Filed: 06/27/2001
• Issued: 07/11/2006
• Est. Priority Date: 06/27/2001
• Status: Expired due to Term

• Current Assignee: Honeywell Incorporated (Honeywell International Inc.)
• Original Assignee: Honeywell Incorporated (Honeywell International Inc.)
• Inventors: Wood, Roland A.
• Primary Examiner(s): Gabor, Otilia
• Application Number:
  US09/893,066
• Publication Number:
  US 20030001093A1
• Time in Patent Office: 1,840 Days
• Field of Search: 250/332, 250/208.1, 250/226, 250/216, 250/573, 250/339.05, 257/442, 257/440, 257/461, 257/78
• US Class Current: 250/332
• CPC Class Codes: G01J 2005/0077 Imaging
• CPC Class Codes: G01J 3/36 Investigating two or more bands of a spectrum by separate detectors
• CPC Class Codes: G01J 3/513 having fixed filter-detector pairs
• CPC Class Codes: G01J 5/0022 for sensing the radiation of moving bodies
• CPC Class Codes: H01L 27/14621 Colour filter arrangements
• CPC Class Codes: H01L 27/14647 Multicolour imagers having a stacked pixel-element structure, e.g. npn, npnpn or MQW elements
• CPC Class Codes: H01L 27/1465 of the hybrid type
• CPC Class Codes: H01L 27/14652 Multispectral infrared imagers, having a stacked pixel-element structure, e.g. npn, npnpn or MQW structures
• CPC Class Codes: H04N 23/11 for generating image signals from visible and infrared light wavelengths
• CPC Class Codes: H04N 25/131 including elements passing infrared wavelengths
• CPC Class Codes: H04N 25/134 based on three different wavelength filter elements
• CPC Class Codes: H04N 5/33 Transforming infrared radiation cameras or camera modules for generating image signals from infrared radiation H04N23/20; circuitry of SSIS for transforming infrared radiation into image signals H04N25/20

Abstract

A dual wavelength focal plane has a first array of infrared sensing pixel elements and a second array of visible light pixel elements adapted to be selective to colors encountered while driving an automobile. The second array is selective to the colors red, blue and green, so being selective to traffic control signals, including brake lights of other automobiles. The arrays are vertically stacked on a monolithic silicon substrate. The arrays are electrically coupled to a processor and display to integrate the infrared and color pixel elements into a view for a driver of the automobile.

Claims

1. A dual wavelength focal plane comprising:

a first array of infrared sensing microbolometer pixel elements;

a second array of visible light pixel elements responsive to selective colors encountered while driving an automobile such that traffic control colors are optimally sensed.

2. The focal plane of claim 1 wherein the second array is selective to the color red.

3. The focal plane of claim 1 wherein the second array is selective to the colors red, green and blue.

4. The focal plane of claim 1 wherein the first and second arrays are fabricated on a monolithic silicon substrate.

5. The focal plane of claim 1 and further comprising a visible light filter that passes red light to the second array of visible light pixel elements.

6. The focal plane of claim 1 and further comprising multiple filters for selectively passing red, green and blue light to the second array of visible light pixel elements.

7. A dual wavelength focal plane comprising:

a first array of infrared sensing microbolometer pixel elements;

a second array of sets of three pixel elements optimally selective to red, blue and green respectively such that traffic control colors are optimally sensed.

8. A sensor for aiding an automobile driver at night, the sensor comprising:

a first array of infrared sensing microbolometer pixel elements formed on a silicon substrate;

a second array of sets of three visible sensors optimally responsive to red, blue and green respectively, each set of photosensors formed on the silicon substrate beneath the infrared sensing pixel element such that traffic control colors are optimally sensed.

9. A night display system for an automobile, the system comprising:

a first array of infrared sensing microbolometer pixel elements;

a second array of photosensors responsive to traffic control signals; and

,

a heads up display coupled to the arrays for generating an image based on infrared images and visible light corresponding to traffic control signals.

10. A method of providing a heads up display for enhancing visibility for night time drivers of vehicles, the method comprising:

sensing infrared radiation sources generally in the path of the vehicle using a microbolometer;

selectively sensing visible radiation corresponding to traffic control colors; and

combining the sensed visible radiation and infrared radiation to provide images for the heads up display, wherein the traffic control colors are displayed in color.

11. The method of claim 10 wherein an array of infrared sensors are used to sense the infrared radiation, and an array of silicon photosensors are used to sense selected colors.

12. The method of claim 11 wherein the arrays are vertically integrated into a monolithic silicon substrate to optimize fill factor.

13. A method of forming a dual wavelength focal plane, the method comprising:

forming an array of visible light pixel elements optimally selective to colors encountered while driving an automobile, the array being formed on a silicon substrate; and

forming an array of infrared sensing microbolometer pixel elements on top of the array of visible light pixel elements, wherein the infrared sensing pixel elements pass visible light to the array of visible light pixel elements.

14. The method of claim 13, and further comprising forming red, amber and green visible light filters corresponding to the visible light pixel elements.

15. A dual wavelength focal plane comprising:

a first array of infrared sensing microbolometer pixel elements allowing transmission of visible light;

a second array of visible light pixel elements selective to vehicle traffic control colors; and

a thermally isolating space between the first and second arrays.

16. A dual wavelength focal plane comprising:

a first array of infrared sensing microbolometer pixel elements allowing transmission of visible light;

a second array of visible light pixel elements;

a third array of filters positioned above the second array of visible light pixel elements to make such pixel elements selective to vehicle traffic control colors; and

a thermally isolating space between the first and third arrays.

17. The focal plane of claim 16 wherein the first and second arrays are fabricated on a monolithic silicon substrate.

18. The night display system of claim 17 and further comprising a processor coupled to the arrays and the heads up display controlling the display to show infrared

sensed images in monochrome, and visible light sensed images in color.

19. A night display system for an automobile, the system comprising:

a first array of infrared sensing substantially transparent microbolometer pixel elements;

a second array of visible light pixel elements selective to vehicle traffic control colors;

a thermally isolating space between the first and second arrays;

a heads up display coupled to the arrays for generating an image based on infrared images and visible light corresponding to traffic control signals.