Imaging device and visual recognition support system employing imaging device

• US 7,656,423 B2
• Filed: 08/12/2003
• Issued: 02/02/2010
• Est. Priority Date: 08/30/2002
• Status: Expired due to Fees

• Current Assignee: Panasonic Corporation (Panasonic Holdings Corporation)
• Original Assignee: Matsushita Electric Industrial Company Limited (Panasonic Holdings Corporation), Toyota Jidosha Kabushiki Kaisha (Toyota Motor Corporation)
• Inventors: Kawamata, Shinya, Hagisato, Yasuo, Yamaguchi, Ryuji, Mimura, Hidetoshi, Kumasaka, Tsuyoshi
• Primary Examiner(s): Tran; Sinh
• Assistant Examiner(s): Cutler; Albert H
• Application Number:
  US10/638,369
• Publication Number:
  US 20040042683A1
• Time in Patent Office: 2,366 Days
• Field of Search: 348/217.1, 348/148, 348/187, 348/188, 348/223.1, 348254-256, 348/229.1
• US Class Current: 348/148
• CPC Class Codes: G06V 10/10 Image acquisition document image scanning and transmission H04N1/00; control of digital cameras H04N23/60
• CPC Class Codes: H04N 23/72 Combination of two or more compensation controls
• CPC Class Codes: H04N 23/73 by influencing the exposure time
• CPC Class Codes: H04N 23/76 by influencing the image signals

Abstract

An imaging device stores and photoelectric-converts incoming light from an object of which an image is to be captured with a CCD, and controls an output level of a picture signal obtained by signal processing an image signal output from the CCD. An output adjustment value of the picture signal in the output control is set to become 50 to 70 IRE according to a peak value of the picture signal when a test pattern is captured under standard conditions. Accordingly, it is possible to have a typical imaging device display a captured image darker, and thus enable imaging suitable for nighttime imaging and the like.

Claims

1. An imaging device for a visual recognition support system that provides visual recognition support to a driver when driving a first vehicle at night, the imaging device comprising:

an image pickup device which stores and photoelectric-converts incoming light from an object of which an image is to be captured and which is sensitive to a near-infrared light; and

an output control device which controls an output level of a picture signal obtained by signal processing an image signal output from the image pickup device,

wherein the output control device controls the output level of the picture signal output from the imaging device such that the peak value becomes 50 to 70 IRE when a predetermined test pattern is captured under a standard condition, so that an effect from the halation of headlights is reduced while sufficient visibility of pedestrians is ensured if there is a pedestrian and an oncoming, second vehicle with its headlight on in a captured image, and

a final picture, based on the picture signal, having the peak value of 50 to 70 IRE, is displayed in the first vehicle.

2. The imaging device according to claim 1, wherein the output control device controls the output level of the picture signal by changing a light storage time of the image pickup device based on the image signal.

3. The imaging device according to claim 1, wherein the standard condition includes:

1) a chart light source apparatus that emits light having a color temperature of 5100±

100°

K, an illumination intensity of 2750±

150 LUX, and a luminance of 1050±

50 mt (cd/m2), and

     2) a room lighting set between 500 to 1500 LUX.

4. The imaging device according to claim 1, wherein a grayscale chart is used for the test pattern.

5. The imaging device of claim 1, wherein the peak value of the picture signal is controlled to be about 65 IRE.

6. The imaging device of claim 5, wherein the peak value of the picture signal is controlled to be between ±

3 IRE of 65 IRE.

7. An imaging device for a visual recognition support system that provides visual recognition support to a driver when driving a first vehicle at night, the imaging device comprising:

an image pickup device which stores and photoelectric-converts incoming light from an object of which an image is to be captured and which is sensitive to a near-infrared light; and

an output control device which controls an output level of a picture signal obtained by signal processing an image signal output from the image pickup device,

wherein when a peak value of a signal wave of the picture signal exceeds a predetermined value, the output control device controls the output level of the picture signal output from the imaging device such that the peak value becomes 50 to 70 IRE, so that an effect from the halation of headlights is reduced while sufficient visibility of pedestrians is ensured if there is a pedestrian and an oncoming, second vehicle with its headlight on in a captured image, and

a final picture, based on the picture signal, having the peak value of 50 to 70 IRE, is displayed in the first vehicle.

8. The imaging device according to claim 7, wherein the output control device controls the output level of the picture signal by adjusting a gain of an amplifier that amplifies the picture signal.

9. The imaging device of claim 7, wherein the peak value of the picture signal is controlled to be about 65 IRE.

10. The imaging device of claim 9, wherein the peak value of the picture signal is controlled to be between ±

3 IRE of 65 IRE.

11. An imaging device for a visual recognition support system that provides visual recognition support to a driver when driving a first vehicle at night, the imaging device comprising:

an image pickup device which stores and photoelectric-converts incoming light from an object of which an image is to be captured and which is sensitive to a near-infrared light; and

output controlling means for controlling an output level of a picture signal obtained by signal processing an image signal output from the image pickup device,

wherein the output controlling means controls the output level of the picture signal output from the imaging device such that the peak value becomes 50 to 70 IRE when a predetermined test pattern is captured under a standard condition, so that an effect from the halation of headlights is reduced while sufficient visibility of pedestrians is ensured if there is a pedestrian and an oncoming, second vehicle with its headlight on in a captured image, and

a final picture, based on the picture signal, having the peak value of 50 to 70 IRE, is displayed in the first vehicle.

12. An imaging device for a visual recognition support system that provides visual recognition support to a driver when driving a first vehicle at night, the imaging device comprising:

an image pickup device which stores and photoelectric-converts incoming light from an object of which an image is to be captured and which is sensitive to a near-infrared light; and

output controlling means for controlling an output level of a picture signal obtained by signal processing an image signal output from the image pickup device,

wherein when a peak value of a signal wave of the picture signal exceeds a predetermined value, the output controlling means controls the output level of the picture signal output from the imaging device such that the peak value becomes 50 to 70 IRE, so that an effect from the halation of headlights is reduced while sufficient visibility of pedestrians is ensured if there is a pedestrian and an oncoming, second vehicle with its headlight on in a captured image, and

a final picture, based on the picture signal, having the peak value of 50 to 70 IRE, is displayed in the first vehicle.