Arrangement for locating radiaring sources

• US 4,193,689 A
• Filed: 07/25/1978
• Issued: 03/18/1980
• Est. Priority Date: 07/29/1977
• Status: Expired due to Term

• Current Assignee: Thomson-CSF
• Original Assignee: Thomson-CSF
• Inventors: Reymond, Jean-Claude, Hidalgo, Jean-Luc
• Primary Examiner(s): Buczinski, S. C.
• Application Number:
  US05/927,821
• Time in Patent Office: 602 Days
• Field of Search: 356/141, 356/152
• US Class Current: 356/139.03
• CPC Class Codes: F41G 3/225 Helmet sighting systems
• CPC Class Codes: G01B 11/26 for measuring angles or tapers; for testing the alignment of axes
• CPC Class Codes: G01S 5/163 Determination of attitude using inertial means G01C9/00; control of attitude G05D1/49

Abstract

A sensor system for determining the spatial location of radiation relative to the sensor including three unit sensors each having a cylindrical optical lens and a linear array of photosensitive elements positioned in the focal plane at a fixed angle with respect to the longitudinal axis of the lens. Each lens determines substantially a plane of radiation passing through the source. The unit sensors are arranged to define three separate planes having the radiation source being detected as common point. The detected signals are processed to identify respectively the serial position of the elements activated by the focused radiation. Ancillary calculating means calculates the location of the source from the serial position information. By detecting a plurality of sources coupled to a movable body, the present invention enables the user to continuously determine the direction of a fixed axis of the movable body.

Claims

1. A sensor system for the spatial location of radiation sources comprising:

first, second and third unit sensors, each such unit sensor including;

an optical device of the cylindrical lens type for focusing light radiation incoming from a point source defining a plane of reception of said light radiation passing through said source and the longitudinal optical axis of said optical device, and

a linear array of photosensitive elements for developing detection signals responsive to said light radiation, said elements positioned in the corresponding focal plane of said optical device at an angle with respect to said longitudinal axis,

said first, second and third unit sensors having arrays arranged in a plane, the arrays of said first and second sensors being aligned in a first cartesian reference direction and the array of said third sensor being oriented in a second cartesian reference direction and situated between said first and second unit sensors,

circuit means for processing said detection signals of said detecting arrays to identify respectively the rank position of the elements activated by said radiation; and

ancillary calculating means for calculating the spatial location of said source common to said planes from the identification.

2. A sensor system according to claim 1, wherein for each unit sensor the array is arranged with an orientation orthogonal to that of the longitudinal axis of the associated optical device.

3. A sensor system according to claim 1, wherein each unit sensor includes an optical filter for filtering the radiation from said source, which is intended to lie in a predetermined spectral band.

4. A sensor system according to claim 1, wherein said array of photosensitive elements includes CCD circuits and wherein for each unit sensor, said processing circuits comprise:

a counting circuit for counting synchronizing pulses which are used for the scanning of the array in order to bring about the identification of rank position,

a threshold comparison circuit for detecting the level of the detected signals,

a first detection circuit fo selecting the leading edge of said detected signal, and

a second detection circuit coupled in parallel with said first detection circuit for selecting the trailing edge of said detected signal, the leading edge signal operating a switching circuit which receives said synchronizing pulses and a second signal of half the frequency to change over the counting frequency, the trailing edge signal causing the count to stop so that the result of counting will correspond to the serial position of the center one of the activated elements.

5. A sensor system according to claim 1, including two detection assemblies arranged at a predetermined distance from one another in a cartesian reference direction to define a triangle with a point source to localize each detection assembly comprisng three unit sensors.

6. A sensor system for the spatial location of radiation sources comprising:

first, second and third unit sensors, each such unit sensor including;

an optical device of the cylindrical lens type for focusing light radiation incoming from a point source defining a plane of reception of said light radiation passing through said source and the longitudinal optical axis of said optical device, and

a linear array of photosensitive elements for developing detection signals responsive to said light radiation, said elements positioned in the corresponding focal plane of said optical device at an angle with respect to said longitudinal axis,

said first, second and third unit sensors having arrays arranged in a plane, the arrays of said first and second sensors being aligned in a first cartesian reference direction and the array of said third sensor being oriented in a second cartesian reference direction and situated between said first and second unit sensors;

circuit means for processing said detection signals of said detecting arrays to identify respectively the rank position of the elements activated by said radiation, said circuit means for processing including;

a counting circuit for counting synchronizing pulses used for the scanning of the array in order to bring about the identification of rank position,

a threshold comparison circuit for detecting the level of the detected signals,

a first detection circuit for selecting the leading edge of said detected signal, and

a second detection circuit coupled in parallel with said first detection circuit for selecting the trailing edge of said detected signal, the leading edge signal operating a switching circuit which receives said synchronizing pulses and a second signal of half the frequency to change over the counting frequency, the trailing edge signal causing the count to stop so that the result of counting will correspond to the serial position of the center one of the activated elements; and

ancillary calculating means for calculating the spatial location of said source common to said planes from the identification.

7. A sensor system according to claim 6, wherein said arrays of photosensitive elements include CCD circuits and wherein each array is arranged with an orientation orthogonal to that of the longitudinal axis of the associated optical device.