Stereo camera

• US 10,291,903 B2
• Filed: 01/07/2015
• Issued: 05/14/2019
• Est. Priority Date: 02/14/2014
• Status: Active Grant

• Current Assignee: Hitachi Astemo Ltd. (Hitachi, Ltd.)
• Original Assignee: Hitachi Automotive Systems Limited (Hitachi, Ltd.)
• Inventors: Sasada, Yoshiyuki, Ohsumi, Ken, Matsuura, Kazuo
• Primary Examiner(s): Harold, Jefferey F
• Assistant Examiner(s): Satti, Humam M
• Application Number:
  US15/102,010
• Publication Number:
  US 20160309138A1
• Time in Patent Office: 1,588 Days
• Field of Search: None
• CPC Class Codes: B60R 11/04 Mounting of cameras operative during drive; Arrangement of controls thereof relative to the vehicle
• CPC Class Codes: G01C 3/085 with electronic parallax measurement
• CPC Class Codes: G03B 35/08 by simultaneous recording
• CPC Class Codes: G03B 7/00 Control of exposure by setting shutters, diaphragms or filters, separately or conjointly control of exposure in television cameras by means of circuitry influencing the optical part of the camera H04N23/75
• CPC Class Codes: H04N 13/239 using two 2D image sensors having a relative position equal to or related to the interocular distance H04N13/243 takes precedence
• CPC Class Codes: H04N 17/002 for television cameras
• CPC Class Codes: H04N 23/45 for generating image signals from two or more image sensors being of different type or operating in different modes, e.g. with a CMOS sensor for moving images in combination with a charge-coupled device [CCD] for still images
• CPC Class Codes: H04N 23/50 Constructional details
• CPC Class Codes: H04N 23/56 provided with illuminating means

Abstract

In order to obtain a low-cost stereo camera which can decrease the load of software-based calibration, a stereo camera is provided with a first vehicle-mounted camera which comprises a first lens unit and a first imaging element, and a second vehicle-mounted camera which comprises a second lens unit and a second imaging element. This stereo camera is characterized in that the first imaging element has a first sensitivity value recording unit in which sensitivity values of the first imaging element are recorded, and the second imaging element has a second sensitivity value recording unit in which sensitivity values of the second imaging element are recorded, wherein the sensitivity variation width between the sensitivity values of the first imaging element recorded in the first sensitivity value recording unit and the sensitivity values of the second imaging element recorded in the second sensitivity value recording unit is within a preset reference width.

Claims

1. A stereo camera comprising:

a first vehicle-mounted camera comprising a first lens unit and a first image sensor configured to perform imaging via the first lens unit; and

a second vehicle-mounted camera comprising a second lens unit and a second image sensor configured to image via the second lens unit,

wherein the first image sensor has a first sensitivity value memory in which a sensitivity value of the first image sensor is recorded,

wherein the second image sensor has a second sensitivity value memory in which a sensitivity value of the second image sensor is recorded,

wherein a sensitivity variation width between the sensitivity value of the first image sensor recorded in the first sensitivity value memory and the sensitivity value of the second image sensor recorded in the second sensitivity value memory is within a predetermined reference width, wherein the sensitivity values are transmittance values,

wherein the first lens unit comprises a first optical information memory in which a sensitivity value of the first lens unit is recorded,

wherein the second lens unit comprises a second optical information memory in which a sensitivity value of the second lens unit is recorded, and

wherein whichever of the first image sensor and the second image sensor has a lower sensitivity value is combined with whichever of the first lens unit and the second lens unit has a higher sensitivity value.

2. The stereo camera according to claim 1,

wherein the first lens unit and the second lens unit have, respectively, diaphragms fixed at aperture values different from each other, and

out of the first image sensor and the second image sensor, the lens unit combined with the image sensor having the higher sensitivity value has the higher aperture value of the diaphragm than the lens unit combined with the image sensor having the lower sensitivity value.

3. The stereo camera according to claim 2,

wherein when the first vehicle-mounted camera and the second vehicle-mounted camera receive light from a predetermined light source, a difference between a first signal level output from the first image sensor and a second signal level output from the second image sensor is within a predetermined specified range.

4. The stereo camera according to claim 1,

wherein, when the sensitivity value of the second image sensor is equal to or less than the sensitivity value of the first image sensor and the sensitivity value of the second lens unit is higher than the sensitivity value of the first lens unit, the second image sensor is combined with the second lens unit, and

when the sensitivity value of the second image sensor is equal to or more than the sensitivity value of the first image sensor and the sensitivity value of the second lens unit is lower than the sensitivity value of the first lens unit, the second image sensor is combined with the second lens unit.