Method and apparatus for locating and measuring the distance to a target

• US 20080266541A1
• Filed: 04/27/2007
• Published: 10/30/2008
• Est. Priority Date: 04/27/2007
• Status: Active Grant

• Current Assignee: Robert Bosch LLC (Robert Bosch GmbH)
• Original Assignee: Robert Bosch LLC (Robert Bosch GmbH)
• Inventors: Chan, Sai Chak, Yung, Wai Lam, Ng, Kwong Lam, Bittner, Wilfried Alois Anton, Chan, Wah Pong, Lam, Yat Wah, Zimmerman, Thomas Paul Richard
• Granted Patent: US 7,855,778 B2
• Time in Patent Office: Days
• US Class Current: 356/4.01
• CPC Class Codes: G01S 17/08 for measuring distance only indirect measurement G01S17/46; active triangulation systems G01S17/48
• CPC Class Codes: G01S 17/86 Combinations of lidar systems with systems other than lidar, radar or sonar, e.g. with direction finders
• CPC Class Codes: G01S 7/4813 Housing arrangements

Abstract

Embodiments of the invention comprise an apparatus for use with a laser range finder configured to direct a laser beam toward a scene to measure the distance to a target in the scene and having a range finder display for displaying data, including data that is indicative of the distance to a target, wherein the apparatus comprises a protective housing, a camera module in the housing, the camera module including a lens mounted in a front end portion of the housing, and a light path through the lens to image sensor, an image sensor operatively connected to the camera module for receiving images acquired by the camera module, electronic memory for selectively storing data of images from the image sensor, circuitry for controlling the operation of the image sensor and the memory, a camera display in the housing operatively connected to the image sensor for receiving the image data and providing a visual display of the image, and a switch for storing image data in the memory. Other embodiments include a projector in the housing for projecting the data displayed by the second display onto the image sensor to thereby capture the image data of the scene and displayed distance data together.

Claims

1. Apparatus for use with a portable handheld laser range finder configured to direct a laser beam toward a scene to measure the distance to a target in the scene and having a range finder display for displaying data, including data that is indicative of the distance to a target, said apparatus comprising:

a protective housing configured to receive and retain the range finder;

a camera module in said housing, said camera module including a lens mounted in a front end portion of said housing, and a light path through said lens to an image sensor;

an image sensor operatively connected to said camera module for receiving images acquired by said camera module;

electronic memory for selectively storing data of images from said image sensor;

circuitry for controlling the operation of said image sensor and said memory;

a camera display in said housing operatively connected to said image sensor for receiving said image data and providing a visual display of said image; and

a switch for storing image data in said memory.

2. Apparatus as defined in claim 1 further comprising a projector operatively connected to said housing for projecting said data displayed by the range finder display onto said image sensor to thereby enable capture of said image data of said scene and displayed distance data together.

3. Apparatus as defined in claim 2 wherein said projector has an elongated portion extending from the camera module over the range finder display and a multiply angled light path from above the range finder display through said elongated portion and a plurality of lenses and mirrors to said image sensor.

4. Apparatus as defined in claim 3 wherein a half mirror is positioned adjacent said image sensor and is configured to reflect the image data of said scene onto said image sensor and to transmit the range finder display image data through said half mirror, so that both said image data of said scene and the range finder display image data is simultaneously captured by said image sensor.

5. Apparatus as defined in claim 3 wherein a pivotable mirror is positioned adjacent said image sensor and is configured to reflect the image data of said scene onto said image sensor and to block the range finder display image data from reaching said image sensor when pivoted into a first position, and to enable said the range finder display image data to be directed to said image sensor and block said image data of said scene when pivoted to a second position.

6. Apparatus as defined in claim 1 wherein said image sensor comprises a multiplicity of pixels arranged in a x by y matrix, said image having a predefined center coordinate and an image area of pixels surrounded by a border having a width of at least a predetermined number of pixels, said control circuitry being configured to shift said predefined center coordinate and said image area within said matrix, so that said image area can occupy a portion of said border for calibration purposes.

7. Apparatus as defined in claim 6 wherein said border width has a sufficient number of pixels to permit at least 2 degrees of angular adjustment of said image area of pixels within said pixel matrix.

8. Apparatus as defined in claim 6 said image sensor has at least 5 megapixels and the width of said border is at least approximately 170 pixels.

9. Apparatus as defined in claim 1 wherein said image sensor is a CMOS imaging sensor having at least 5 megapixels.

10. Apparatus as defined in claim 9 wherein said laser beam is selected to be one of red, green or blue and said imaging sensor has an approximately equal number of red, green and blue color filters for said pixels to provide red, green and blue outputs, said control circuitry being operative to attenuate the outputs of the non-selected color during a calibration operation to increase the visibility of a laser spot in an acquired scene.

11. Apparatus as defined in claim 6 wherein said control circuitry for selectively generating overlay indicia identifying said center coordinate of said scene on said camera display.

12. Apparatus as defined in claim 11 wherein said indicia comprises a cross hair configuration that identify said center coordinate.

13. Apparatus as defined in claim 1 wherein said camera display is a LCD display.

17. Apparatus as defined in claim 1 wherein said laser beam is one of red, green and blue, said apparatus further comprising a bandpass filter of the same color that is selectively moveable into and out of said light path of to filter the image acquired by said image sensor.

18. Apparatus as defined in claim 1 wherein said control circuitry is configured to control said image sensor to provide a digital zoom function to selectively enlarge a portion of an acquired scene as displayed on said camera display.

19. Apparatus as defined in claim 18 wherein said camera display is an LCD display comprising 240 by 320 pixels, said maximum enlargement of said enlarged portion has one pixel of said image sensor corresponding to one pixel of said LCD.

20. Apparatus as defined in claim 2 wherein said image data from said image sensor is stored in a predetermined file and said distance data are stored in a predetermined companion file, whereby the location and/or names of the two files identify the files as being linked together.

22. Apparatus as defined in claim 20 further comprising a projector in said housing for projecting said data displayed by said second display onto said image sensor to thereby capture said image data of said scene and displayed distance data together.

14. Apparatus for use with a laser range finder configured to direct a laser beam toward a scene to measure the distance to a target in the scene and having a range finder display for displaying data, including data that is indicative of the distance to a target, said apparatus comprising:

a protective housing;

a camera module in said housing, said camera module including a lens mounted in a front end portion of said housing, and a light path through said lens to an image sensor;

an image sensor operatively connected to said camera module for receiving images acquired by said camera module;

electronic memory for selectively storing data of images from said image sensor;

circuitry for controlling the operation of said image sensor and said memory;

a camera display in said housing operatively connected to said image sensor for receiving said image data and providing a visual display of said image; and

a switch for storing image data in said memory

wherein said housing comprises an expandable and retractable top front portion that is mounted to a base portion by a folding mechanism, whereby when said top front portion is in an open position, said camera display is visible beneath said top front portion and said camera is positioned to acquire an image, and whereby when said top front portion is in a closed position, said top front portion is retracted and said camera and camera display are enclosed in said housing.

15. Apparatus as defined in claim 14 wherein said top front portion contains said camera module, said camera display, said control circuitry, a battery compartment, said camera lens and a key pad for operating said camera module.

16. Apparatus as defined in claim 14 wherein said housing has a compartment rearwardly of said top front portion configured to receive the range finder therein, said housing having a side clamp that is movable outwardly from one side of said housing for loading the range finder in said compartment, said side clamp having at least one spring for biasing said side clamp inwardly to firmly hold the range finder in said compartment.

21. Apparatus for finding a target and measuring the distance to the target, comprising:

a protective housing;

a camera module in said housing, a lens mounted in a front end portion of said housing, and a light path through said lens;

a first display in said housing operatively connected to said camera module for receiving said image data and providing a visual display of said image;

an image sensor;

electronic memory for selectively storing data of images from said image sensor;

control circuitry for controlling said image sensor and electronic memory to selectively acquire image data of a scene and store the same;

a laser distance finder in said housing configured to direct a laser beam toward said scene and generate data that is indicative of the distance to a target in said scene;

a second display in said housing operatively connected to said distance finder for displaying distance data;

a switch for storing image data in said memory.

23. A method of calibrating a laser spot produced by a laser range finder directed to a target to a predetermined coordinate within an image area captured by a target finder having a video camera with a megapixel image sensor having a matrix of pixels that is larger than the image area and a display for displaying the captured image area, the target finder having circuitry for controlling the operation of the image sensor and display and input controls to the circuitry, said method comprising:

selectively providing inputs to the circuitry to shift the location of the pixels of the image area to move the image area so that the laser spot is displayed at the predetermined coordinate.

24. A method as defined in claim 23 wherein said inputs are provided by actuating directional switches which incrementally move said displayed image until said laser spot is displayed at the predetermined coordinate.

25. A method of actuating the visibility of indicia having a selected one of the colors of red, blue or green that is being displayed on a display wherein the input signals to the display originate from a megapixel imaging sensor that has an approximately equal number of red, green and blue color filters for said pixels to provide red, green and blue outputs, and wherein control circuitry controls the operation of the image sensor and display, said method comprising:

operating the control circuitry to attenuate the output signals of the two non-selected colors.