Electronic endoscope with color adjustment function

• US 6,943,822 B2
• Filed: 06/11/2002
• Issued: 09/13/2005
• Est. Priority Date: 06/15/2001
• Status: Active Grant

• Current Assignee: Hoya Corporation
• Original Assignee: Pentax Corporation (Hoya Corporation)
• Inventors: Iida, Mitsuru, Iriyama, Kenichi, Hibi, Haruhiko
• Primary Examiner(s): Rao, Andy
• Application Number:
  US10/165,989
• Publication Number:
  US 20030001952A1
• Time in Patent Office: 1,190 Days
• Field of Search: 348 65- 76
• US Class Current: 348/65
• CPC Class Codes: H04N 1/6086 by scene illuminant, i.e. conditions at the time of picture capture, e.g. flash, optical filter used, evening, cloud, daylight, artificial lighting, white point measurement, colour temperature
• CPC Class Codes: H04N 23/88 for colour balance, e.g. white-balance circuits or colour temperature control

Abstract

An electronic endoscope includes a video-scope with an image sensor and a video-processor, to which the video-scope is detachably connected. The electronic endoscope has a light source that emits illuminating light for illuminating a subject, a color adjuster that performs a color adjustment process for color image signals read from the image sensor, which include a plurality of color signal components corresponding to a plurality of color elements, and a light source detector that detects the type of the light source. The color adjuster performs the color adjustment process in accordance with the type of the light source such that color in displayed subject image is properly reproduced.

Claims

1. An electronic endoscope including a video-scope with an image sensor and a video-processor, to which said video-scope is detachably connected, said electronic endoscope comprising:

a light source that emits illuminating light for illuminating a subject, color image signals corresponding to the subject, which include a plurality of color signal components corresponding to a plurality of color elements, being read from said image sensor;

a color adjuster that performs a color adjustment process for the color image signals to generate video signals; and

a light source detector that detects the type of said light source,

wherein said color adjuster performs the color adjustment process in accordance with the type of said light source such that color in a displayed subject image is properly reproduced.

2. The electronic endoscope of claim 1, wherein said color adjuster is provided in said video-scope.

3. The electronic endoscope of claim 2, wherein said video-scope includes a color adjustment data memory for storing a series of color adjustment data corresponding to plural types of light source, and

wherein a set of color adjustment data corresponding to the type of said light source is selected from the series of color adjustment data and read from said color adjustment data memory, and said color adjuster performs the color adjustment process in accordance with the set of color adjustment data.

4. The electronic endoscope of claim 3, wherein said light source is provided in said video-processor, said color adjuster has a memory area for loading and storing the set of color adjustment data, said video-processor has a light source memory for storing light source data, and said video-scope includes a data setter that sets the set of color adjustment data to said memory area,

wherein said light source detector detects the type of said light source in accordance with the light source data and said data setter sets the set of color adjustment data corresponding to the light source data when said video-scope is connected to said video-processor.

5. The electronic endoscope of claim 1, wherein said light source is one of a xenon lamp, a metal halide lamp, and a halogen lamp, and said lamp detector detects the type of said lamp by detecting which lamp of said xenon lamp, said metal halide lamp, and said halogen lamp is being used.

6. The electronic endoscope of claim 1, wherein said color adjuster includes a white balance adjuster that adjusts a relative ratio of R, G, B signal components, generated from the color image signals, by gain-control.

7. The electronic endoscope of claim 1, wherein said color adjuster includes:

a primary color signal generator that generates primary color image signals composed of R signal components corresponding to the color Red, G signal components corresponding to the color Green, and B signal components corresponding to the color Blue, on the basis of the color image signals read from said image sensor;

a white balance adjuster that adjusts a relative ratio of the R, G, B signal components in the primary color signals by gain-control;

a gamma corrector that performs a gamma correction for the white balance adjusted primary color image signals; and

a video signal generator that generates the video signals including luminance signals and color difference signals on the basis of said gamma corrected primary color image signals.

10. The electronic endoscope of claim 1, wherein said light source detector detects the type of said light source from a plurality of light sources.

8. A video-scope provided in an electronic endoscope having a light source for illuminating a subject, said video-scope having an image sensor and being detachably connected to a video-processor, color image signals corresponding to the subject, which include a plurality of color signal components corresponding to a plurality of color elements, being read from said image sensor, said video-scope comprising:

a color adjuster that performs a color adjustment process for the color image signals to generate video signals; and

a light source detector that detects the type of said light source,

wherein said color adjuster performs the color adjustment process in accordance with the type of said light source such that color in a displayed subject image is properly reproduced.

9. The video-scope of claim 8, wherein said light source detector detects the type of said light source from a plurality of light sources.