MEDICAL INSTRUMENT
A processor includes: first to third matrix circuits that generate an image signal of normal light and an image signal of special light based on an output of a CCD that picks up an image of returning light of light that is irradiated onto living tissue; a color discrimination circuit that discriminates a color tone for respective pixels in accordance with a luminance level of an image signal of the special light; and a color correction circuit that, in an observation mode that uses special light, if an observation object other than living tissue is discriminated as being a red color tone based on the color discrimination circuit, performs color correction to a yellow color tone that is similar to a color tone that the observation object other than living tissue is discriminated as being in an observation mode that uses normal light.
1 . A medical instrument, comprising:
image signal generation means that generates an image signal of normal light and an image signal of special light based on an output of image pickup means that picks up an image of returning light of light that is irradiated onto living tissue by illumination means;
color discrimination means that discriminates a color tone for respective pixels in accordance with a luminance level of an image signal of the special light, and discriminates whether or not the respective pixels correspond to an observation object other than the living tissue; and
color correction means that, in an observation mode that uses the special light, if an observation object other than the living tissue is discriminated as being a red color tone based on the color discrimination means, performs color correction to a yellow color tone that is similar to a color tone that the observation object other than the living tissue is discriminated as being in an observation mode that uses the normal light.
2 . The medical instrument according to claim 1 , wherein a luminance level of an image signal of the special light is a luminance level of an RGB signal.
3 . The medical instrument according to claim 1 , wherein when the color discrimination means discriminates an observation object other than the living tissue as being a green color tone or a blue-green color tone, the color correction means performs the color correction to a blue color tone.
4 . The medical instrument according to claim 1 , wherein:
the illumination means switchably irradiates the normal light and the special light; and
the image signal generation means generates an image signal of the special light that is irradiated onto the living tissue by the illumination means.
5 . The medical instrument according to claim 4 , wherein the special light is light of two narrow bands for observing a blood vessel in accordance with a depth of a living body mucous membrane.
6 . The medical instrument according to claim 5 , wherein the illumination means irradiates light of a third narrow band that has a wavelength band that is different from the two narrow bands of light and that is selected based on spectral characteristics of an observation object other than the living tissue and spectral characteristics of hemoglobin in the living tissue.
7 . The medical instrument according to claim 1 , wherein:
the illumination means irradiates the normal light; and
the image signal generation means generates an image signal of the special light by spectral estimation processing based on the returning light of the normal light.
8 . The medical instrument according to claim 1 , wherein, with respect to a color of an observation object other than the living tissue, the color correction means changes a correction parameter in the color correction in accordance with a luminance level of an image signal of the special light from the image pickup means.
9 . The medical instrument according to claim 1 , wherein, with respect to a color of an observation object other than the living tissue, the color correction means performs the color correction processing by matrix calculation using a matrix of correction coefficients.
10 . The medical instrument according to claim 1 , wherein the color correction means divides hue into ten regions, and performs color correction processing based on the ten hue regions.
11 . The medical instrument according to claim 1 , wherein the medical instrument is a processor for an endoscope that processes an endoscopic image.
12 . The medical instrument according to claim 1 , wherein the medical instrument is a capsule endoscope.
13 . A medical instrument, comprising:
illumination means that switchably irradiates normal light and light of two narrow bands for observing a blood vessel in accordance with a depth of a living body mucous membrane onto living tissue, and also irradiates light of a third narrow band that has a wavelength band that is different from the two narrow bands of light and that is selected based on spectral characteristics of an observation object other than the living tissue and spectral characteristics of hemoglobin in the living tissue;
image signal generation means that generates an image signal of the normal light and an image signal of the special light based on an output of image pickup means that picks up an image of returning light of light that is irradiated onto living tissue by the illumination means;
color discrimination means that discriminates a color tone for respective pixels in accordance with a luminance level of image signals of the light of two narrow bands and the light of a third narrow band, and discriminates whether or not the respective pixels correspond to an observation object other than the living tissue; and
color correction means that, in an observation mode that uses the special light, based on a discrimination result of the color discrimination means, performs color correction with respect to a color of an observation object other than the living tissue so that the color of the observation object other than the living tissue is similar to a color thereof in an observation mode that uses the normal light.
14 . The medical instrument according to claim 13 , wherein center wavelengths of the light of two narrow bands are 415 nm and 540 nm, and a center wavelength of the light of a third narrow band is 630 nm.