Digital micro-mirror based image simulation system

• US 5,457,493 A
• Filed: 09/15/1993
• Issued: 10/10/1995
• Est. Priority Date: 09/15/1993
• Status: Expired due to Fees

• Current Assignee: Texas Instruments, Inc.
• Original Assignee: Texas Instruments, Inc.
• Inventors: Sampsell, Jeffrey, Delong, James A., Florence, James M., Lin, Tsen-Hwang, Leddy, Michael, Boysel, Mark
• Primary Examiner(s): Britton, Howard W.
• Application Number:
  US08/121,710
• Time in Patent Office: 755 Days
• Field of Search: 348/164, 348/181, 348/187
• US Class Current: 348/164
• CPC Class Codes: G02B 26/0841 the reflecting element being moved or deformed by electrostatic means
• CPC Class Codes: H04N 17/00 Diagnosis, testing or measuring for television systems or their details
• 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

An image simulation system 20 for testing sensor systems 26 and for training image sensor personnel wherein synthetic image data is generated by a scene generator 21 and projected by an image projector 23. The image projector 23 uses a digital micromirror device array 27 to modulate the incident energy and create an image. Four modulation schemes are discussed including digital pulse-width modulation, phase contrast modulation, full complex modulation, and analog modulation. The digital pulse width modulation technique will typically require synchronizing the image sensor and the image projector. Phase contrast modulation, full complex modulation, and analog modulation do not require synchronizing the image projector 23 and the sensor system 26. Phase contrast modulation and full complex modulation have the capability to produce phase information within the image. The image simulation system 20 can produce high contrast images and is more flexible than prior art system.

Claims

1. An image simulation system for providing a non-visible image for use by an image detection system, the image simulation system comprising:

a scene generator providing an electronic representation of a scene;

a source of non-visible radiant energy providing a beam of radiant energy traveling along a first path; and

an array of flexure beam micromirror elements receiving the electronic representation from the scene generator and reflecting the beam of radiant energy along a second path, wherein each element of the array is deflected according to the electronic representation, each deflected element phase-modulating a portion of the beam of radiant energy.

2. The system of claim 1 wherein said non-visible radiant energy source is an infrared source.

3. The system of claim 1 further comprising:

an image detection system receiving the reflected beam of radiant energy; and

an environmental simulator providing environmental stimuli to the image detection system to simulate dynamic operating conditions.

4. The system of claim 1 further comprising:

a first lens focusing the reflected beam onto a transform plane, wherein a zeroth-order component of the reflected beam and a higher-order component of the reflected beam are physically separated on the transform plane;

a phase plate in the transform plane of the reflected beam, the phase plate shifting the phase of the zeroth-order component of the reflected beam; and

a second lens receiving the reflected beam from the phase plate and focusing the reflected beam onto an image plane, wherein the phase-shifted zeroth-order component interferes with higher-order component to form an amplitude modulated image.

5. The system of claim 1 further comprising:

a lens focusing the reflected beam onto an image plane, wherein portions of the reflected beam modulated by adjacent micromirror elements interfere to form an amplitude modulated image.

6. The system of claim 1 wherein said beam of radiant energy is coherent.

7. A method of creating a non-visible image for detection by an image sensor, the method comprising:

generating an electronic representation of a scene;

deflecting an array of flexure beam micromirror elements in response to the electronic representation of a scene;

reflecting a beam of radiant energy from the array of deflected micromirror elements;

forming an image with the reflected beam of radiant energy; and

extracting information from the image with an image sensor.

8. The method of claim 7, wherein the forming step comprises:

focusing the reflected beam of radiant energy onto a transform plane to spatially separate the zeroth-order component from the higher-order component; and

phase shifting the zeroth-order component of the reflected beam to form an amplitude modulated beam of radiant energy.

9. The method of claim 7, wherein the forming step comprises:

focusing the reflected beam of radiant energy onto an image plane such that portions of the reflected beam of radiant energy modulated by adjacent micromirror elements interfere and form an amplitude modulated image.

10. The method of claim 7 further comprising the step of simulating environmental forces acting upon the image sensor.

11. The method of claim 7 further comprising the steps of:

providing the extracted information to an operator; and

modifying the operation of the image sensor based on a feedback signal from the operator.

12. The method of claim 7 wherein the beam of radiant energy is coherent.

13. An image simulation system for providing a non-visible image for use by an image detection system, the image simulation system comprising:

a scene generator providing an electronic representation of a scene;

a source of non-visible radiant energy providing a beam of radiant energy traveling along a first path;

an array of micromirror elements receiving the electronic representation from the scene generator and reflecting the beam of radiant energy along a second path, wherein each element of the array is deflected according to the electronic representation;

a projection lens focusing the reflected radiant energy reflected into an image such that the radiant energy reflected by each micromirror element forms an image pixel; and

wherein each micromirror element is continuously variable between a first position wherein all radiant energy reflected by the element enters the projection lens and forms a bright pixel, and a second position wherein none of the radiant energy reflected by the element enters the projection lens thereby forming a dim pixel.

14. The system of claim 13 wherein said non-visible radiant energy source is an infrared source.

15. The system of claim 13 further comprising:

an image detection system receiving the image; and

an environmental simulator providing environmental stimuli to the image detection system to simulate dynamic operating conditions.

16. The system of claim 13 wherein said beam of radiant energy is coherent.

17. A method of creating a non-visible image for detection by an image sensor, the method comprising:

generating an electronic representation of a scene;

deflecting an array of micromirror elements in response to the electronic representation of a scene;

reflecting a beam of radiant energy from the array of deflected micromirror elements;

focusing the reflected beam of radiant energy to form an image comprised of an array of image pixels, wherein the amount of radiant energy reflected from a micromirror element and focused onto an image pixel is determined by the amount the micromirror element is deflected; and

extracting information from the image with an image sensor.

18. The method of claim 17 further comprising the step of simulating environmental forces acting upon the image sensor.

19. The method of claim 17 further comprising the steps of:

providing the extracted information to an operator;

modifying the operation of the image sensor based on a feedback signal from the operator.

20. The method of claim 17 wherein the beam of radiant energy is coherent.