Telecentric 3D camera and method

• US 6,091,905 A
• Filed: 12/19/1997
• Issued: 07/18/2000
• Est. Priority Date: 06/22/1995
• Status: Expired due to Term

• Current Assignee: Microsoft International Holdings BV (Microsoft Corporation)
• Original Assignee: 3DV Systems Ltd. (Microsoft Corporation)
• Inventors: Iddan, Gavriel, Yahav, Giora
• Primary Examiner(s): Gray, David M.
• Application Number:
  US08/981,359
• Time in Patent Office: 942 Days
• Field of Search: 348/143-147, 356/1, 356/2, 356/4.07, 356/5-5.01, 356/141-141.2, 356/141.4, 356/141.5, 356/152-152.1, 396/106, 396/429
• US Class Current: 396/106
• CPC Class Codes: G01C 11/025 by scanning the object
• CPC Class Codes: G01S 15/89 for mapping or imaging
• CPC Class Codes: G01S 17/02 Systems using the reflection of electromagnetic waves other than radio waves G01S17/66 takes precedence
• CPC Class Codes: G01S 17/08 for measuring distance only indirect measurement G01S17/46; active triangulation systems G01S17/48
• CPC Class Codes: G01S 17/18 wherein range gates are used
• CPC Class Codes: G01S 17/88 Lidar systems specially adapted for specific applications
• CPC Class Codes: G01S 17/894 3D imaging with simultaneous measurement of time-of-flight at a 2D array of receiver pixels, e.g. time-of-flight cameras or flash lidar
• CPC Class Codes: G01S 17/931 of land vehicles
• CPC Class Codes: G01S 17/933 of aircraft or spacecraft
• CPC Class Codes: G01S 7/4802 using analysis of echo signal for target characterisation; Target signature; Target cross-section
• CPC Class Codes: G01S 7/4812 transmitted and received beams following a coaxial path
• CPC Class Codes: G01S 7/4817 relating to scanning
• CPC Class Codes: G01S 7/51 Display arrangements
• CPC Class Codes: G02B 7/32 using active means, e.g. light emitter including both an active and a passive focus detecting device G02B7/285; using ultrasound G02B7/40

Abstract

Apparatus for creating an image indicating distances to objects in a scene. The invention is comprised of a radiation source and modulator, telecentric optics for receiving and collimating the radiation reflected from the scene, a detector and a processor. The detector receives the collimated, reflected radiation and sends a signal to the processor. The processor forms an image having an intensity value distribution indicative of the distance of objects form the apparatus.

Claims

1. Apparatus for creating an image indicating distances to objects in a scene, comprising:

a modulated source of radiation, which directs radiation toward a scene, such that a portion of the radiation from the source is reflected from the scene and reaches the apparatus;

telecentric optics which receive and collimate radiation reflected from the scene;

a modulator which modulates the collimated radiation, such that a part of the portion of the radiation which reaches the apparatus is passed by the modulator, the part being dependent on the distance of respective portions of the scene from the apparatus;

a detector which detects an image formed from the modulated collimated radiation; and

a processor which forms an image having an intensity value distribution indicative of the distance of objects from the apparatus, responsive to the intensity distribution of the detected image.

2. Apparatus according to claim 1 wherein the source and detector are boresighted.

3. Apparatus according to claim 2 wherein the source of radiation comprises a continuous source of radiation which is modulated by the same modulator as the detected radiation.

5. Apparatus according to any of the preceding claims and including a focusing lens which receives the modulated collimated radiation and focuses it onto the detector.

6. Apparatus according to any of claims 1-4 wherein the modulator is an electro-optical modulator.

7. Apparatus according to any of claims 1-4 wherein the modulator is a KDP modulator.

8. Apparatus according to any of claims 1-4 wherein the modulator is an acousto-optical device.

4. Apparatus for creating an image indicating distances to objects in a scene, comprising:

a modulated source of radiation, which directs radiation toward a scene along an axis, such that a portion of the radiation from the source is reflected from the scene and reaches the apparatus;

telecentric optics which receive radiation reflected from the scene and collimate it along said axis;

a modulator which modulates the collimated radiation such that a part of the portion of the radiation which reaches the apparatus is passed by the modulator, the part being dependent on the distance of respective portions of the scene from the apparatus;

a detector which detects an image formed by the modulated collimated radiation; and

a processor which forms an image having an intensity value distribution indicative of the distance of objects from the apparatus, responsive to the intensity distribution of the detected image.