Range finding camera

• US 5,225,876 A
• Filed: 12/21/1990
• Issued: 07/06/1993
• Est. Priority Date: 12/23/1989
• Status: Expired due to Fees

• Current Assignee: Dornier Luftfahrt GmbH Postfach
• Original Assignee: Dornier Luftfahrt GmbH
• Inventors: Lux, Peter, Eibert, Max
• Primary Examiner(s): ADAMS JR, RUSSELL E
• Application Number:
  US07/632,051
• Time in Patent Office: 928 Days
• Field of Search: 354/403, 354/110, 354/113, 356/2, 356/4, 356/5, 356/375, 356/376, 358/95, 358/107, 352/39
• US Class Current: 396/109
• CPC Class Codes: G01S 17/89 for mapping or imaging
• CPC Class Codes: G01S 7/4815 using multiple transmitters
• CPC Class Codes: G01S 7/4817 relating to scanning
• CPC Class Codes: G01S 7/4818 using optical fibres

Abstract

The camera includes two functionally equivalent line and field scanners, one for issuing a light pulse that will be returned by an object point, and identified by a particular line/field scanning position in both scanners; the second scanner being attuned to recognize the returned light in one scanning raster point only for purposes of correlation. The field scan is realized through a deflecting mirror or in a columnal array the line scans are either solid state or fiber optics.

Claims

1. A camera for obtaining a two dimensional range image of a field of view, comprising:

a light source means;

a first, two dimensional scanning means for distributing light from the light source means into a two dimensional scanning array and including line and field scan for obtaining the distributing of the light in said field of view, serially and on a point by point basis, to produce a series of light pulses reflected by different points in the field of view;

a second, two dimensional scanning means operating synchronously with the first scanning means for receiving light from the different points of and within the field of view according to the two dimensional scanning array of the first scanning means as duplicated by the second scanning means, and including signal means for the detection of arrival times of light as received by the second scanning means in accordance with the line and field scan by both of the scanning means;

at least one of the scanning means including a fiber optical line scanner having one fiber ends arranged in a line and being further provided with a rotating optical element at opposite fiber ends, the latter fiber ends at the opposite end being arranged in a circle and being optically coupled to the rotating optical element;

the field scanning of the first and the second scanning means being a shared movable optical element; and

evaluating means connected to the first scanning means and to the signal means of the second scanning means for detecting the transit time of light pulses as fed by the first scanning means to the individual points in the field of view and as returned back by the points in the field of view to the second scanning means and for each point in the field of view separately for obtaining a two dimensional range image of that field of view.

2. Range finder imaging camera according to claim 1, said first and second two dimensional scanning means including a common field scan in terms of a movable reflector means.

3. A range imaging camera as in claim 2, one of the scanning means being a solid state linear array.

4. A camera for obtaining a two dimensional range image of a field of view comprising:

first scanning means for generating a light scan signal in the configuration of a light pulses that emanate, one pulse at a time, respectively from a plurality of exit windows, these light exit windows being arranged in a line;

second scanning means positioned for receiving reflected light signals, one at a time and through respective ones of a plurality of light entrance windows, also arranged in a line and in physical relation to the line of the plurality of exit windows so as to obtain an entrance window-to-exit window correspondence through a field of view in which the light pulses are reflected;

means connected to the first and second scanning means for operating them in synchronism so that a light scan signal that emerges from a particular exit window of the first scanning means and has been reflected by a point in the field of view towards the second scanning means, enters a particular entrance window of the second scanning means and is so recognized as having emanated from a particular exit window at a particular instant;

field scan means for operationally causing the light scan signals as emanating from the first scanning means and the reflected signal as received by the second scanning means, to be deflected transversely to the respective line scanning by the first and second line scanning means thereby scanning transversely to the line scan in the field of view; and

means connected to the first and second scanning means for detecting as to each signal that emanates from an exit window and enters an entrance window a transit time and generating, point by point as to the field of view, a two dimensional range image, from the relative transit times of light signals as emanating from the first scanning means and as received by the second scanning means.

5. Range imaging camera as in claim 4, said field scan means including deflectable mirror means for deflecting the light pulses that emanate from the exits of the first scanning means transverse to the respective line and for directing a correspondingly reflected light signal to the respective light entrance window of the second scanning means.

6. Range imaging camera as in claim 4, at least one of said first and second scanning means including fiber optic means arranged with one end along the respective line and with a respective other end in a circle concentric to a particular point, there being rotating means for directing light as between said circle and said center point.

7. A range imaging camera as in claim 4, at least one of said first and second scanning means being a linear electronic array.

8. A range imaging camera as in claim 4, wherein said field scan means is integrated in said first and second means and that said the first scanning means has a two dimensional array of light exits and said second scanning means has a two dimensional array of light entrance windows.

9. A range imaging camera as in claim 4, said first and second scanning means including common coaxial optic means cooperating with field scan means.

10. A camera for obtaining a two dimensional range image of a field of view comprising:

a light source means;

a first, solid state two dimensional scanning means for distributing light from the light source means into a two dimensional scanning array and including line and field scan for obtaining the distributing of light in a field of view, serially on a point by point basis to produce a series of light pulses reflected by different points in the field of view;

a second, solid state two dimensional scanning means operating synchronously with the first scanning means for receiving light from the different points of and within the field of view according to the two dimensional scanning array of the first scanning means as duplicated by the second scanning means, and including means for the detection of arrival times of light as received by the second scanning means in accordance with the line and field scan by both the scanning means; and

evaluating means connected to the two scanning means for detecting the transit time of light pulses as fed by the first scanning means to the individual points in the field of view and as returned back by the points in the field of view to the second scanning means and for each point in the field of view separately for obtaining a two dimensional range image of that field of view.

11. A camera for obtaining a two dimensional range image, of a field of view comprising:

a light source means;

a first line scanning means for distributing light from the light source means in a one dimensional scanning array, serially and on a point by point basis to produce a series of light pulses to be reflected by different points in a field of view;

a second line scanning means operating synchronously with the first scanning means, for receiving light from the different points of and within the field of view according to the one dimensional scanning array of the first scanning means as duplicated by the second scanning means, and including means for the detection of arrival times of light as received by the second scanning means in accordance with the line and field scan by both the scanning means;

field scan means interposed between the first and second line scan means to deflect the light as distributed by the first scanning means prior to reflection by the field of view and again subsequent to that reflection but prior to receiving by the second line scanning means; and

evaluating means connected to the two scanning means for detecting the transit time of light pulses as fed by the first scanning means to the individual points in the field of view and as returned back by the points in the field of view to the second scanning means and for each point in the field of view separately for obtaining a two dimensional range image of that field of view.

12. A camera as in claim 11, at least one of the line scanning means including a fiber optical line scanner having one fiber ends arranged in a line and being further provided with a rotating optical element at an opposite fiber end the fiber ends at the opposite end being arranged in a circle.

13. A camera as in claim 11, at least one of the line scan means being a linear solid state device.