Multimode Optical Sensor

• US 20100328645A1
• Filed: 08/18/2008
• Published: 12/30/2010
• Est. Priority Date: 08/17/2007
• Status: Active Grant

• Current Assignee: Princeton Satellite Systems Incorporated
• Original Assignee: Princeton Satellite Systems, Inc.
• Inventors: Bhatta, Pradeep, Paluszek, Michael A.
• Granted Patent: US 8,081,302 B2
• Time in Patent Office: Days
• US Class Current: 356/9
• CPC Class Codes: G01C 3/08 Use of electric radiation detectors
• CPC Class Codes: G01S 17/26 wherein the transmitted pulses use a frequency-modulated or phase-modulated carrier wave, e.g. for pulse compression of received signals
• CPC Class Codes: G01S 17/42 Simultaneous measurement of distance and other co-ordinates indirect measurement G01S17/46
• CPC Class Codes: G01S 17/87 Combinations of systems using electromagnetic waves other than radio waves
• CPC Class Codes: G01S 7/4811 common to transmitter and receiver
• CPC Class Codes: G01S 7/4813 Housing arrangements
• CPC Class Codes: G01S 7/483 Details of pulse systems

Abstract

A Multimode Optical Sensor (MMOS) is a laser radar (ladar) that employs both coherent, or heterodyne, and noncoherent detection at long range, i.e. ranges for which the target is no more than a pixel in dimension. Coherent detection provides much higher velocity resolution while the noncoherent detection can provide better detectability.

Claims

1. An optical sensor for measuring relative position, velocity, attitude and attitude rate of a satellite comprising:

a laser capable of emitting coherent electromagnetic radiation;

a coherent detector;

an energy detector;

a telescope having a primary and a secondary mirror;

a first beamsplitter situated to direct a first portion of said emitted coherent electromagnetic toward said coherent detector and to direct a second portion of said emitted coherent electromagnetic radiation toward said secondary mirror of said telescope;

a second beamsplitter situated to direct a first portion of light collected by said primary mirror of said telescope and relayed via said secondary mirror to said beamsplitter to said coherent detector and a second portion of said collected light to said energy detector.

2. The optical sensor of claim 1 wherein said primary mirror and said secondary mirror of said telescope are arranged in a Nasmyth configuration.

3. The optical sensor of claim 1 wherein said primary mirror and said secondary mirror of said telescope are arranged in a Cassegrain configuration.

4. The optical sensor of claim 1 wherein said primary mirror and said secondary mirror of said telescope are arranged in a Coude configuration.

5. The optical sensor of claim 1 further including a two dimensional imaging chip.

6. The optical sensor of claim 5 wherein the two dimensional imaging chip is a charged coupled device.

7. The optical sensor of claim 5 wherein the two dimensional imaging chip is a charge injection device.

8. The optical sensor of claim 5 wherein the two dimensional imaging chip is a complementary metal oxide semiconductor chip.

9. The optical sensor of claim 5 further comprising a two dimensional scanning mirror.