WO2021019663A1

WO2021019663A1 - Endoscope light source device and endoscope device

Info

Publication number: WO2021019663A1
Application number: PCT/JP2019/029754
Authority: WO
Inventors: 麦穂大道寺; 雄亮矢部; 伊藤　毅
Original assignee: オリンパス株式会社
Priority date: 2019-07-30
Filing date: 2019-07-30
Publication date: 2021-02-04

Abstract

An endoscope light source device (105) includes a light source unit (100) having four or more light sources for emitting four or more lights having mutually different peak wavelengths, and a light source control unit (312) whereby the quantity of light emitted by each of the four or more light sources can be adjusted independently. The four or more light sources include three lights having peak wavelengths respectively in the blue region, the green region, and the red region constituting the visible-light region. The four or more light sources include a narrow-band light source for generating narrow-band light having a peak wavelength in a blood-vessel-emphasizing wavelength region, and a wide-band light source for generating wide-band light having a peak wavelength in a wavelength region other than the blood-vessel-emphasizing wavelength region. The full width at half maximum of the blood-vessel-emphasizing wavelength region is centered at the peak wavelength in a predetermined color region of the absorption spectrum of hemoglobin.

Description

Light source device for endoscopes and endoscope device

The present invention relates to a light source device for an endoscope, an endoscope device, and the like.

In an endoscope device, a method of constructing a pseudo white illumination light by combining a plurality of light sources that generate light in different bands is known. Patent Document 1 includes a light source device including two laser diodes that generate light in the blue region, two laser diodes that generate light in the red region, and an LED (Light Emitting Diode) that generates light in the green region. Is disclosed.

International Publication No. 2018/008185

In an endoscope device, in order to capture an image having excellent visibility of blood vessels and color reproducibility of a subject such as a mucous membrane, there is a problem of generating illumination light suitable for the image. In Patent Document 1 described above, only narrow band light by a laser diode is used in the blue region and the red region. Therefore, in the method of Patent Document 1, it is difficult to obtain the color reproducibility of the mucous membrane in the blue region and the red region as compared with the case of using wideband light.

One aspect of the present invention includes a light source unit having four or more light sources that emit four or more lights having different peak wavelengths from each other, and a light source control unit that can independently adjust the amount of light emitted by each of the four or more light sources. The four or more lights include three lights having peak wavelengths in each of the blue region, the green region, and the red region constituting the visible light region, and the four or more light sources are in the blood vessel-enhanced wavelength region. A narrow band light source that generates narrow band light having a peak wavelength and a wide band light source that generates wide band light having a peak wavelength in a wavelength region other than the blood vessel emphasized wavelength region are included, and the blood vessel emphasized wavelength region is a hemoglobin. It is related to a light source device for an endoscope, which is a wavelength region having a half-value width centered on the peak wavelength of the light absorption spectrum.

Further, another aspect of the present invention relates to an endoscopic device including the above-mentioned light source device for an endoscope.

Configuration example of a light source device for an endoscope and an endoscope device. An example of the first spectrum of 5-band illumination light. A second spectrum example of 5-band illumination light. An example of the third spectrum of 5-band illumination light. An example of the fourth spectrum of 5-band illumination light. An example of the fifth spectrum of 5-band illumination light. An example of the sixth spectrum of 5-band illumination light. Example of the 7th spectrum of 5-band illumination light. 9 (A) to 9 (D) are other spectral examples of the 5-band illumination light. 10 (A) to 10 (C) are other spectral examples of the 5-band illumination light. 11 (A) to 11 (D) are other spectral examples of the 5-band illumination light. An example of the first spectrum of 6-band illumination light. An example of the second spectrum of 6-band illumination light. An example of the third spectrum of 6-band illumination light. 15 (A) to 15 (D) are other spectral examples of the 6-band illumination light. 16 (A) to 16 (C) are examples of other spectra of 6-band illumination light. 17 (A) to 17 (D) are other spectral examples of the 6-band illumination light. 18 (A) to 18 (D) are other spectral examples of the 6-band illumination light. The figure explaining the light emission timing in the surface sequential system, and the image processing for the captured image.

Hereinafter, this embodiment will be described. The present embodiment described below does not unreasonably limit the content of the present invention described in the claims. Moreover, not all of the configurations described in the present embodiment are essential constituent requirements of the present invention.

1. 1. Endoscope Light Source Device, Endoscope Device FIG. 1 is a configuration example of an endoscope light source device 105 and an endoscope device 10 including the light source device 105 for an endoscope. The endoscope device 10 includes a light source device 105 for an endoscope, a scope 200, a processing unit 310, a display unit 400, and an operation unit 500. The endoscope device is a device that makes it possible to observe the inside of the observation target by inserting a scope inside the observation target. As the endoscope device 10, for example, a flexible mirror used for a gastrointestinal tract or the like can be assumed, but the endoscope device 10 is not limited to this, and the endoscope device 10 may be a rigid mirror used for a laparoscope or the like.

The endoscope light source device 105 is a device that generates and controls illumination light, and includes a light source unit 100 and a control unit 314.

The light source unit 100 is a device that generates illumination light. The light source unit 100 is also called a light source device. The light source unit 100 generates white illumination light by generating light in a plurality of bands using a plurality of light sources. The light source unit 100 generates white light in the WLI (White Light Imaging) mode. Further, the light source unit 100 may be configured to generate special light in the special light mode. The emission timing of the illumination light may be either a simultaneous type in which a plurality of light sources are simultaneously emitted, or a surface sequential type in which a plurality of light sources are sequentially emitted. The details of the light source unit 100 will be described later.

The control unit 314 includes a light source control unit 312 that controls the light source unit 100. The light source control unit 312 controls the light emission timing of a plurality of light sources included in the light source unit 100 and the amount of light of each light source. Further, the light source control unit 312 generates white light or special light in the light source unit 100 according to the WLI mode or the special light mode set via the operation unit 500. The control unit 314 may further have a function of controlling each unit of the endoscope device 10. For example, the control unit 314 may control the imaging timing of the imaging unit 250 in synchronization with the light emission timing of the light source. Further, the control unit 314 may instruct the processing unit 310 of the content of image processing according to the WLI mode or the special light mode set via the operation unit 500. Of the functions of the control unit 314, functions other than the light source control unit 312 may be included in the processing unit 310.

The scope 200 is inserted into the body and images the subject. The subject in this embodiment is in the body cavity of a living body, for example, the mucous membrane of the digestive tract. The scope 200 includes a light guide 210, an illumination lens 220, and an image pickup unit 250. The scope 200 has a connector (not shown), which is attached to and detached from the endoscope light source device 105 and the processing unit 310.

The light guide 210 guides the illumination light from the light source unit 100 to the tip of the scope 200. The illumination lens 220 irradiates the subject with the illumination light ILM guided by the light guide 210.

The imaging unit 250 includes an objective lens, an image sensor, and an A / D conversion circuit. The reflected scattered light RSL from the subject is incident on the objective lens, and the objective lens forms an image of the subject. The image sensor outputs an imaging signal by capturing the subject image. The A / D conversion circuit A / D-converts the analog imaging signal from the image sensor into a digital imaging signal. The A / D conversion circuit may be built in the image sensor. The image sensor may be either a color image sensor provided with a color filter for each pixel or a monochrome image sensor. The color image sensor is, for example, a Bayer type image sensor having a Bayer array color filter, or a complementary color image sensor having a complementary color filter.

The processing unit 310 performs image processing. Further, as described above, the processing unit 310 may control each unit of the endoscope device. The processing unit 310 is also called a processing circuit or a processor. The processing unit 310 receives an imaging signal from the imaging unit 250, performs image processing on the imaging signal to generate a display image, and outputs the display image to the display unit 400. Hereinafter, the R channel, G channel, and B channel of the imaging signal are referred to as a red imaging signal, a green imaging signal, and a blue imaging signal, respectively. In the WLI mode, the processing unit 310 generates a display image by inputting a red image pickup signal, a green image pickup signal, and a blue image pickup signal to the R channel, the G channel, and the B channel of the display image, respectively. The processing unit 310 may generate a special light image in the special light mode. Further, as will be described later in FIG. 19 and the like, when light of a plurality of bands is sequentially emitted in the same color region, the imaging signals corresponding to the plurality of bands are combined, and the combined imaging signal is used as the corresponding channel of the display image. You may enter it.

The display unit 400 is a device that displays the display image from the processing unit 310. The display unit 400 is, for example, a liquid crystal display device or the like. The operation unit 500 is a device that receives an operation on the endoscope device 10 from the user. For example, the operation unit 500 is a button, a dial, a pointing device, a touch panel, a foot switch, or the like.

Next, a detailed configuration example of the light source unit 100 will be described. The light source unit 100 includes a light source driving unit 110, light sources LSA to LSF, and an optical combine unit 120. Although the case where the light source unit 100 includes six light sources will be described here as an example, the light source unit 100 may include four or more light sources.

The light source control unit 312 outputs a control signal indicating the light emission timing and the amount of light of each light source to the light source drive unit 110. The light source driving unit 110 outputs a driving signal DRS to the light sources LSA to LSF based on the control signal. For example, the light source drive unit 110 outputs a drive current as a drive signal DRS, and controls the amount of light emitted from the light source by the amount of the drive current. The light source control unit 312 can independently adjust the amount of light emitted from each light source. That is, the light source control unit 312 can arbitrarily adjust the light amount ratio of the light emitted by the light sources LSA to LSF.

The light sources LSA to LSF emit light having different spectra. Specifically, the light sources LSA to LSF emit light having different peak wavelengths from each other. The light source unit 100 is a hybrid light source that combines a narrow band light source and a wide band light source. That is, each of the light sources LSA to LSF is a narrow band light source that emits narrow band light or a wide band light source that emits wide band light, and the light sources LSA to LSF are at least one narrow band light source and at least one wide band light source. including. Narrow band light is light whose half width is narrower than a predetermined bandwidth. On the other hand, broadband light is light whose full width at half maximum is wider than a predetermined bandwidth. The predetermined bandwidth is, for example, 20 nm. The narrowband light source is, for example, a laser diode. The broadband light source is, for example, an LED (Light Emitting Diode). Alternatively, the broadband light source is a combination of an LED and a phosphor excited by the LED. Alternatively, the broadband light source is a combination of a laser diode and a phosphor excited by the laser diode.

The optical combining unit 120 combines the optical LSL emitted by the light sources LSA to LSF, and causes the combined optical CBL to be incident on the light guide 210. The optical combiner 120 is composed of, for example, a dichroic mirror and a lens. Alternatively, the optical merging unit 120 may be an optical fiber that emits light incident from a plurality of incident ends to one emitting end.

2. 2. Illumination light spectrum The light source unit 100 has four or more light sources that emit four or more lights having different peak wavelengths from each other. The light source control unit 312 can independently adjust the amount of light emitted by each of the four or more light sources. At this time, the four or more lights include three lights having peak wavelengths in each of the blue region, the green region, and the red region constituting the visible light region. The four or more light sources include a narrow band light source that generates narrow band light having a peak wavelength in the blood vessel emphasized wavelength region, and a wide band light source that generates wide band light having a peak wavelength in a wavelength region other than the blood vessel emphasized wavelength region. .. That is, at least one of the four or more lights may be narrow band light, and at least one of the other may be wide band light. The blood vessel-enhanced wavelength region is a wavelength region having a half-value width centered on the peak wavelength in a predetermined color region of the light absorption spectrum of hemoglobin. The predetermined color region may be any of a blue region, a green region, and a red region. Further, the peak wavelength may be a wavelength of a local peak having an absorption coefficient larger than that of the surroundings, and is not limited to the wavelength of the peak having the maximum absorption coefficient in a predetermined color region.

In this way, a hybrid light source that combines a narrow band light source and a wide band light source can be realized. Since three lights having peak wavelengths are emitted in each of the blue region, the green region, and the red region, a hybrid light source for white light can be realized. Further, since the light source control unit 312 can independently adjust the amount of light emitted by each of the four or more light sources, the illumination light can be adjusted to the color balance of white light. For example, the light intensity ratio of the red region, the green region, and the blue region has a balance target value, and the light source control unit 312 independently adjusts the light intensity of the narrow band light and the wide band light so as to approach the target value. For example, as shown in FIG. 2 described later, it is assumed that there are narrow band light and wide band light in the blue region. In this case, the amount of wideband light may be determined by adjusting the degree of blood vessel enhancement with the amount of narrow band light and subtracting the amount of narrow band light determined thereby from the target value of the amount of light in the blue region.

Further, since narrow band light having a peak wavelength in the blood vessel emphasis wavelength region is emitted, narrow band light having a large light absorption of hemoglobin is emitted. This makes it possible to image blood vessels in the mucous membrane or the like with high contrast as compared with the case of using wideband light in the blood vessel emphasized wavelength region, and it is possible to improve the visibility of blood vessels in the displayed image. Further, since the broadband light having a peak wavelength is emitted in a wavelength region other than the blood vessel emphasized wavelength region, the broadband light is emitted in a region where the light absorption of hemoglobin is relatively small. From the viewpoint of color reproducibility, it is advantageous to obtain wideband information. Therefore, the color reproducibility in the displayed image can be improved by using the wideband light as compared with the case where only the narrowband light is used. From the above, according to the present embodiment, it is possible to realize an illumination light having both blood vessel visibility and color reproducibility.

Further, in the present embodiment, the missing wavelength region between the wavelength region of the narrow band light and the wavelength region of the broadband light included in the same color region of the peak wavelength is narrower than the width of the wavelength region of the broadband light. The width of the wavelength region is a width that is a predetermined ratio of the amount of light to the maximum value of the amount of light in the spectrum of light. For example, the width of the wavelength region is the half width of the spectrum.

For example, as shown in FIG. 2 described later, it is assumed that there is narrow band light and wide band light in the blue region. In this case, the peak wavelength of wideband light and the peak wavelength of narrowband light are included in the same blue region. The missing wavelength region is a wavelength region in which both narrow-band light and wide-band light have zero light intensity. In the example of FIG. 2, there is a missing wavelength region between the narrow band light and the wide band light in the blue region. The width of this missing wavelength region is narrower than the width of the wavelength region of the broadband light in the blue region.

Since the width of the missing wavelength region is narrower than the width of the broadband light in this way, it is possible to reduce the wavelength region in which the amount of light becomes zero in the color region. In the wavelength region where light exists, subject information at that wavelength can be obtained, so that the color reproducibility is improved by reducing the wavelength region where the amount of light is zero.

Hereinafter, the spectrum of the illumination light emitted by the light source unit 100 will be described in detail. First, a spectrum example of the 5-band illumination light will be described with reference to FIGS. 2 to 11 (D). When the illumination light has 5 bands, the light source unit 100 may include the light sources LSA to LSE in FIG. 1. The illumination light may be 4 bands or 6 bands or more. For example, the illumination light may be composed of four types: blue narrow band light, blue wide band light, green wide band light, and red wide band light. An example of the 6-band illumination light will be described later in FIG.

FIG. 2 shows an example of the first spectrum of 5-band illumination light. HBC is a light absorption spectrum of hemoglobin. The vertical axis indicating the absorption coefficient is a logarithmic axis.

In the first spectrum example, the light sources LSA to LSE emit blue narrow band light LBNa, blue wide band light LBBb, green wide band light LGB, first red wide band light LRBa, and second red wide band light LRBb, respectively.

The blue narrow band light LBNa has a peak wavelength in the blood vessel emphasized wavelength region HWA in the blue region BA. The blue region BA is a blue region when the visible light wavelength region is divided into regions of three primary colors, and is, for example, 380 nm to 500 nm. The regions of the three primary colors may have overlapping portions with each other. In the blue region BA, the light absorption spectrum HBC of hemoglobin has a peak PKA. The peak PKA is the position where the absorption coefficient is maximum in the light absorption spectrum HBC of hemoglobin, and its wavelength is 415 nm. The blood vessel-enhanced wavelength region HWA is a wavelength region having a half-value width centered on the wavelength of the peak PKA. The full width at half maximum is the width of the wavelength region which is 1/2 the absorption coefficient of the peak PKA, and is about 30 nm.

The green broadband light LGB has a peak wavelength in the green region GA. The green region GA is a green region when the visible light wavelength region is divided into three primary color regions, and is, for example, 480 nm to 600 nm. The wavelength region of the green broadband light LGB does not have to correspond to the green region GA, and may belong to the green region GA.

The first red broadband light LRBa and the second red wideband light LRBb have a peak wavelength in the red region RA. The red region RA is a red region when the visible light wavelength region is divided into regions of three primary colors, and is, for example, 580 nm to 780 nm.

The first red broadband light LRBa has a peak wavelength in the first mucosal color reproduction wavelength region CRB. The first mucosal color reproduction wavelength region CRB is a wavelength region of the red region RA adjacent to the green region GA. More specifically, the first mucosal color reproduction wavelength region CRB is the minimum value in the light absorption spectrum HBC of hemoglobin in the red region RA and the first peak PKC counted on the shorter wavelength side than the minimum value. This is a wavelength region in which the light absorption spectrum HBC changes sharply. The minimum value of the light absorption spectrum HBC exists in the vicinity of the wavelength of 700 nm. The wavelength of the peak PKC is 580 nm. That is, the first mucosal color reproduction wavelength region CRB is a region in which the light absorption spectrum HBC changes sharply in the range of 580 nm to 700 nm, for example, 580 nm to 610 nm. The steepness means that the slope of the light absorption spectrum HBC is relatively large in the range of 580 nm to 700 nm.

The second red broadband light LRBb has a peak wavelength in the second mucosal color reproduction wavelength region ASB. The second mucosal color reproduction wavelength region ASB is a wavelength region on the longer wavelength side than the first mucous membrane color reproduction wavelength region CRB and has a smaller light absorption of hemoglobin than the first mucosal color reproduction wavelength region CRB. The second mucosal color reproduction wavelength region ASB is, for example, a predetermined wavelength region including the minimum value of the light absorption spectrum HBC, and is, for example, 630 nm to 780 nm.

The blue broadband light LBBb has a peak wavelength in the blue region BA. Specifically, the blue broadband light LBBb has a peak wavelength in the third mucosal color reproduction wavelength region in which the light absorption of hemoglobin is smaller than that in the blood vessel emphasis wavelength region HWA. Specifically, the third mucosal color reproduction wavelength region is a wavelength region in which the absorption coefficient is 1/2 or less of the peak PKA in the light absorption spectrum HBC, and is a wavelength region obtained by excluding the blood vessel-enhanced wavelength region HWA from the blue region BA. Is.

According to the first spectrum example of FIG. 2, the blue narrow band light LBNa can improve the blood vessel visibility, and the wide band light LBBb, LGB, LRBa, and LRBb can improve the color reproducibility. Further, as will be described later, the color reproducibility of red can be further improved by generating the first red broadband light LRBa in the wavelength region where the light absorption spectrum HBC of hemoglobin changes sharply.

FIG. 3 shows an example of the second spectrum of the 5-band illumination light. In the following, the same reference numerals will be given to the elements already described, and the description of the elements will be omitted as appropriate.

In the second spectrum example, the second blue narrow band light LBNb is provided in place of the blue wide band light LBBb of FIG. Specifically, the light sources LSA to LSE emit the first blue narrow band light LBNa, the second blue narrow band light LBNb, the green broadband light LGB, the first red wide band light LRBa, and the second red wide band light LRBb, respectively. The second blue narrow band light LBNb has a peak wavelength in the third mucosal color reproduction wavelength region in which the light absorption of hemoglobin is smaller than that in the blood vessel emphasis wavelength region HWA.

FIG. 4 shows an example of the third spectrum of the 5-band illumination light. In the third spectrum example, the red narrow band light LRNb is provided in place of the second red wide band light LRBb of FIG. Specifically, the light sources LSA to LSE emit blue narrow band light LBNa, blue wide band light LBBb, green wide band light LGB, red wide band light LRBa, and red narrow band light LRNb, respectively. The red narrow band light LRNb has a peak wavelength in the second mucosal color reproduction wavelength region ASB, which absorbs less hemoglobin than the first mucosal color reproduction wavelength region CRB.

FIG. 5 shows an example of the fourth spectrum of 5-band illumination light. In the fourth spectrum example, the second blue narrow band light LBNb is provided in place of the blue wide band light LBBb of FIG. 2, and the red narrow band light LRNb is provided in place of the second red wide band light LRBb of FIG. Specifically, the light sources LSA to LSE emit the first blue narrow band light LBNa, the second blue narrow band light LBNb, the green wide band light LGB, the red wide band light LRBa, and the red narrow band light LRNb, respectively.

FIG. 6 shows an example of the fifth spectrum of the 5-band illumination light. In the fifth spectrum example, the red narrow band light LRNa is provided in place of the first red wide band light LRBa in FIG. Specifically, the light sources LSA to LSE emit blue narrow band light LBNa, blue wide band light LBBb, green wide band light LGB, red narrow band light LRNa, and red wide band light LRBb, respectively. The red narrow-band light LRNa has a peak wavelength in the first mucosal color reproduction wavelength region CRB in which the light absorption spectrum HBC of hemoglobin changes sharply.

FIG. 7 shows an example of the sixth spectrum of the 5-band illumination light. In the sixth spectrum example, the second blue narrow band light LBNb is provided in place of the blue wide band light LBBb in FIG. 2, and the red narrow band light LRNa is provided in place of the first red wide band light LRBa in FIG. Specifically, the light sources LSA to LSE emit the first blue narrow band light LBNa, the second blue narrow band light LBNb, the green broadband light LGB, the red narrow band light LRNa, and the red wide band light LRBb, respectively.

In the spectrum examples of FIGS. 2 to 7, the four or more lights emitted by the light source unit 100 have a blue narrow band light LBNa having a peak wavelength in the blood vessel-enhanced wavelength region HWA in the blue region BA and a peak wavelength in the green region GA. Includes green broadband light LGB and red broadband light having a peak wavelength in the red region RA. The red broadband light here is LRBa or LRBb in FIGS. 2 and 3, LRBa in FIGS. 4 and 5, and LRBb in FIGS. 6 and 7.

The peak PKA having the maximum value in the light absorption spectrum HBC of hemoglobin is included in the blood vessel emphasized wavelength region HWA. By providing the blue narrow-band light LBNa in the blood vessel-enhanced wavelength region HWA, it becomes possible to image the blood vessels of a living body with high contrast, and the blood vessel visibility can be improved. Further, by providing the green broadband light LGB and the red broadband light (LRBa or LRBb), the color reproducibility in the green region and the red region can be improved.

In the spectral examples of FIGS. 2 to 5, the 4 or more lights emitted by the light source unit 100 include the first red broadband light LRBa having a peak wavelength in the first mucosal color reproduction wavelength region CRB.

As described above, the light absorption spectrum HBC of hemoglobin changes sharply in the first mucosal color reproduction wavelength region CRB. Therefore, it is considered that the illumination light in the first mucosal color reproduction wavelength region CRB affects the color reproducibility in a living body containing hemoglobin. According to the spectral examples of FIGS. 2 to 5, by using the first red broadband light LRBa having a peak wavelength in the first mucosal color reproduction wavelength region CRB, the subject has a wide range of the first mucous membrane color reproduction wavelength region CRB. Since the color information can be obtained, the color reproducibility in the red region can be improved. For example, in the first mucosal color reproduction wavelength region CRB, the absorption of hemoglobin is smaller than that in the blue region or the green region, but some absorption occurs. Therefore, in a region where the hemoglobin concentration is high such that blue light or green light is mostly absorbed, the absorption of the first red broadband light LRBa changes according to the shade of hemoglobin and can contribute to color reproducibility.

Further, in the spectral examples of FIGS. 2, 3, 6 and 7, the light of 4 or more emitted by the light source unit 100 includes the second red broadband light LRBb having a peak wavelength in the second mucosal color reproduction wavelength region ASB. ..

As described above, since the second mucosal color reproduction wavelength region ASB is a wavelength region in which the light absorption of hemoglobin is small in the red region RA, the second red broadband light LRBb is hardly absorbed by hemoglobin in the living body. Therefore, since the reflected scattered light from the living body containing hemoglobin contains a relatively large amount of the reflected scattered light of the second red broadband light LRBb, the color reproducibility is improved by using the second red broadband light LRBb. it can.

Further, in the spectrum examples of FIGS. 2, 4, and 6, the four or more lights emitted by the light source unit 100 include blue broadband light LBBb having a peak wavelength in the third mucosal color reproduction wavelength region.

Since the light absorption of hemoglobin in the third mucosal color reproduction wavelength region is smaller than that in the blood vessel-enhanced wavelength region HWA, the blood vessel information is relatively less than that in the blood vessel-enhanced wavelength region HWA. Therefore, by providing the blue broadband light LBBb in the third mucosal color reproduction wavelength region, the color reproducibility in the blue region BA can be improved.

Further, in the spectrum examples of FIGS. 2, 4 and 6, the light source unit 100 includes a blue narrow band light source that emits blue narrow band light LBNa, a blue wide band light source that emits blue wide band light LBBb, and a green wide band light LGB. It includes a green broadband light source that emits light and a red broadband light source that emits a first red broadband light LRBa or a second red broadband light LRBb.

In this way, the blue narrow band light source can improve the blood vessel visibility, and the three wide band light sources can improve the color reproducibility. Further, by providing a wide band light source corresponding to each of the blue region BA, the green region GA, and the red region RA, it is possible to cover a wide spectrum in the visible light region and improve the color reproducibility in the white light image.

Further, in the spectrum example of FIG. 2, the light source unit 100 includes a blue narrow band light source that emits blue narrow band light LBNa, a blue wide band light source that emits blue wide band light LBBb, and a green wide band light source that emits green wide band light LGB. , A first red broadband light source that emits a first red broadband light LRBa, and a second red broadband light source that emits a second red broadband light LRBb.

In this way, the blue narrow band light source can improve the visibility of blood vessels, and the four wide band light sources can improve the color reproducibility in the white light image. Further, by providing the first red broadband light source corresponding to the first mucosal color reproduction wavelength region CRB in which the light absorption spectrum HBC of hemoglobin changes sharply, the color reproducibility can be further improved particularly in the red region.

Further, in the present embodiment, the narrow band light is light whose half width of the spectrum is smaller than the half width centered on the peak wavelength of the light absorption spectrum of hemoglobin. Broadband light is light whose full width at half maximum of the spectrum is larger than the full width at half maximum centered on the peak wavelength of the light absorption spectrum of hemoglobin. Specifically, narrow-band light is light having a spectrum half width smaller than 20 nm. Broadband light is light whose spectrum half width is larger than 20 nm.

In this way, narrow-band light can be generated only in the wavelength region where the absorption of hemoglobin is large, and a high-contrast blood vessel image can be obtained. Further, since the broadband light has a wavelength range wider than the half-value width of the peak of the hemoglobin absorption spectrum, it is possible to cover a wide spectrum range in the light absorption spectrum HBC of hemoglobin and improve the color reproducibility.

Further, in the present embodiment, the narrow band light source is a laser diode. The broadband light source is an LED or a phosphor that generates fluorescence by the light of the LED.

The laser diode can generate narrow band light with a very narrow half width. That is, by using a laser diode as a narrow band light source, narrow band light having a half width smaller than 20 nm can be generated. LEDs or phosphors can generate wideband light with a wider half width than laser diodes. That is, by using an LED or a phosphor that generates fluorescence by the light of the LED as the wideband light source, it is possible to generate wideband light having a half width larger than 20 nm.

FIG. 8 shows an example of the seventh spectrum. In the seventh spectrum example, the green narrow band light LGNb is provided in place of the green wide band light LGB of FIG. Specifically, the light sources LSA to LSE emit blue narrow band light LBNa, blue wide band light LBBb, green narrow band light LGNb, first red wide band light LRBa, and second red wide band light LRBb, respectively.

The green narrow band light LGNb has a peak wavelength in the blood vessel emphasis wavelength region HWB in the green region GA. In the green region GA, the light absorption spectrum HBC of hemoglobin has a peak PKB. The peak PKB is the first peak in the green region GA counting from the short wavelength side, and its wavelength is 540 nm. The blood vessel-enhanced wavelength region HWB is a wavelength region having a half-value width centered on the wavelength of the peak PKB.

Note that the green narrow band light LGNb may have a peak wavelength in the blood vessel emphasis wavelength region HWC in the green region GA. The peak PKC is the second peak counting from the short wavelength side in the light absorption spectrum HBC of hemoglobin in the green region GA, and its wavelength is 580 nm. The blood vessel-enhanced wavelength region HWC is a wavelength region having a half-value width centered on the wavelength of the peak PKC.

According to the spectrum example of FIG. 8, by providing the green narrow band light LGNb in the blood vessel emphasized wavelength region HWB in the green region GA, it is possible to image the blood vessels of the living body with high contrast, and the blood vessel visibility can be improved. Further, by providing narrow-band light LBNa and LGNb in the blood vessel-enhanced wavelength regions HWA and HWB of the two color regions BA and GA having different wavelengths, it becomes possible to image blood vessels having different depths from the biological surface with high contrast. , An image containing more blood vessel information can be captured.

9 (A) to 11 (D) show other spectral examples of the 5-band illumination light. Although the reference numerals indicating the wavelength regions such as the blue region BA are omitted in FIGS. 9A to 11D, the definitions of the respective wavelength regions are as described above.

Also in the spectrum examples of FIGS. 9A to 11D, since the hybrid light source is a combination of narrow band light and wide band light, both blood vessel visibility and color reproducibility in a white light image can be achieved. The effects of each narrow band light and each wide band light are as described in the above spectrum.

In the spectrum example of FIG. 9A, the illumination light includes the first blue broadband light LBBa, the second blue broadband light LBBb, the green narrow band light LGNb, the first red broadband light LRBa, and the second red broadband light LRBb. The blue broadband light LBBa has a peak wavelength in the blood vessel-enhanced wavelength region HWA in the blue region BA.

In the spectrum example of FIG. 9B, the illumination light includes a blue broadband light LBBa, a blue narrow band light LBNb, a green narrow band light LGNb, a first red wide band light LRBa, and a second red wide band light LRBb.

In the spectrum example of FIG. 9C, the illumination light includes the first blue broadband light LBBa, the second blue broadband light LBBb, the green narrow band light LGNb, the red wide band light LRBa, and the red narrow band light LRNb.

In the spectrum example of FIG. 9D, the illumination light includes the first blue broadband light LBBa, the second blue broadband light LBBb, the green narrow band light LGNb, the red narrow band light LRNa, and the red wide band light LRBb.

In the spectrum example of FIG. 10A, the illumination light includes the first blue narrow band light LBNa, the second blue narrow band light LBNb, the green narrow band light LGNb, the first red wide band light LRBa, and the second red wide band light LRBb. Including.

In the spectrum example of FIG. 10B, the illumination light includes blue narrow band light LBNa, blue wide band light LBBb, green narrow band light LGNb, red narrow band light LRNa, and red wide band light LRBb.

In the spectrum example of FIG. 10C, the illumination light includes blue narrow band light LBNa, blue wide band light LBBb, green narrow band light LGNb, red wide band light LRBa, and red narrow band light LRNb.

In the spectrum example of FIG. 11A, the illumination light includes blue narrow band light LBNa, blue wide band light LBBb, green wide band light LGB, first red narrow band light LRNa, and second red narrow band light LRNb.

In the spectrum example of FIG. 11B, the illumination light includes blue broadband light LBBa, blue narrow band light LBNb, green narrow band light LGNb, red narrow band light LRNa, and red wide band light LRBb.

In the spectrum example of FIG. 11C, the illumination light includes blue broadband light LBBa, blue narrow band light LBNb, green narrow band light LGNb, red wide band light LRBa, and red narrow band light LRNb.

In the spectrum example of FIG. 11 (D), the illumination light includes the first blue broadband light LBBa, the second blue broadband light LBBb, the green broadband light LGB, the first red narrow band light LRNa, and the second red narrow band light LRNb. ..

Next, an example of the spectrum of the 6-band illumination light will be described with reference to FIGS. 12 to 18 (D). When the illumination light has 6 bands, the light source unit 100 includes the light sources LSA to LSF in FIG. 1. In the following, the same reference numerals will be given to the elements already described, and the description of the elements will be omitted as appropriate.

FIG. 12 shows an example of the first spectrum of 6-band illumination light. In the first spectrum example, green narrow band light LGNb is further added to the spectrum example of FIG. That is, the light sources LSA to LSF emit blue narrow band light LBNa, blue wide band light LBBb, green wide band light LGB, green narrow band light LGNb, first red wide band light LRBa, and second red wide band light LRBb, respectively.

In the spectrum example of FIG. 12, the light source unit 100 includes a blue narrow band light source, a blue wide band light source, a green wide band light source, a first red wide band light source, and a second red wide band light source, and further includes a green narrow band light source. The green narrow band light source emits green narrow band light LGNb having a peak wavelength in the blood vessel emphasized wavelength region HWB in the green region GA.

By doing so, since the green narrow band light LGNb and the green broadband light LGB are provided in the green region GA, both blood vessel visibility and color reproducibility can be achieved in the green region GA. Further, by providing narrow-band light LBNa and LGNb in the blood vessel-enhanced wavelength regions HWA and HWB of the two color regions BA and GA having different wavelengths, it becomes possible to image blood vessels having different depths from the biological surface with high contrast. , An image containing more blood vessel information can be captured.

FIG. 13 shows an example of the second spectrum of 6-band illumination light. In the second spectrum example, the first green narrow band light LGNa is provided in place of the green broadband light LGB in the spectrum example of FIG. Specifically, the light sources LSA to LSF are blue narrow band light LBNa, blue wide band light LBBb, first green narrow band light LGNa, second green narrow band light LGNb, first red wide band light LRBa, and second red wide band, respectively. Light LRBb is emitted.

The first green narrow band light LGNa has a peak wavelength in the fourth mucosal color reproduction wavelength region in which the light absorption of hemoglobin is smaller than that of the blood vessel emphasized wavelength region HWB in the green region GA. Specifically, the fourth mucosal color reproduction wavelength region is a wavelength region in which the absorption coefficient is 1/2 or less of the peak PKB in the light absorption spectrum HBC, and the blood vessel-enhanced wavelength regions HWB and HWC are excluded from the green region GA. It is a wavelength region.

FIG. 14 shows an example of the third spectrum of the 6-band illumination light. In the third spectrum example, the red narrow band light LRNb is provided in place of the second red wide band light LRBb in the spectrum example of FIG. Specifically, the light sources LSA to LSF emit blue narrow band light LBNa, blue wide band light LBBb, green wide band light LGB, green narrow band light LGNb, red wide band light LRBa, and red narrow band light LRNb, respectively.

According to the spectral examples of FIGS. 12 to 14, the blood vessel visibility can be improved by using the blue narrow band light LBNa and the green narrow band light LGNb, which absorb a large amount of hemoglobin. Further, the color reproducibility can be improved by using the red broadband light LRBa in the wavelength region in which the light absorption spectrum HBC of hemoglobin changes sharply.

15 (A) to 18 (D) show other spectral examples of the 6-band illumination light. In FIGS. 15 (A) to 18 (D), reference numerals indicating wavelength regions such as the blue region BA are omitted, but the definitions of each wavelength region are as described above.

Also in the spectrum examples of FIGS. 15A to 18D, since the hybrid light source is a combination of narrow band light and wide band light, both blood vessel visibility and color reproducibility in a white light image can be achieved. The effects of each narrow band light and each wide band light are as described in the above spectrum.

In the spectrum example of FIG. 15A, the illumination light is the first blue narrow band light LBNa, the second blue narrow band light LBNb, the green wide band light LGB, the green narrow band light LGNb, the first red wide band light LRBa, and the second. Includes red broadband light LRBb.

In the spectrum example of FIG. 15B, the illumination light includes blue narrow band light LBNa, blue wide band light LBBb, green wide band light LGB, green narrow band light LGNb, red narrow band light LRNa, and red wide band light LRBb.

In the spectrum example of FIG. 15C, the illumination light is the first blue broadband light LBBa, the second blue broadband light LBBb, the first green narrow band light LGNa, the second green narrow band light LGNb, and the first red wide band light LRBa. , Second red broadband light LRBb.

In the spectrum example of FIG. 15 (D), the illumination light is blue wideband light LBBa, blue narrowband light LBNb, first green narrowband light LGNa, second green narrowband light LGNb, first red wideband light LRBa, second. Includes red broadband light LRBb.

In the spectrum example of FIG. 16 (A), the illumination light is the first blue broadband light LBBa, the second blue broadband light LBBb, the first green narrow band light LGNa, the second green narrow band light LGNb, the red broadband light LRBa, and red. Includes narrow band light LRNb.

In the spectrum example of FIG. 16B, the illumination light is the first blue broadband light LBBa, the second blue broadband light LBBb, the first green narrow band light LGNa, the second green narrow band light LGNb, the red narrow band light LRNa, Includes red broadband light LRBb.

In the spectrum example of FIG. 16C, the illumination light is the first blue narrow band light LBNa, the second blue narrow band light LBNb, the first green narrow band light LGNa, the second green narrow band light LGNb, and the first red wide band. Includes optical LRBa and second red broadband optical LRBb.

In the spectrum example of FIG. 17 (A), the illumination light is the first blue narrow band light LBNa, the second blue narrow band light LBNb, the green wide band light LGB, the green narrow band light LGNb, the red narrow band light LRNa, and the red wide band light. Includes LRBb.

In the spectrum example of FIG. 17B, the illumination light is the first blue narrow band light LBNa, the second blue narrow band light LBNb, the green wide band light LGB, the green narrow band light LGNb, the red wide band light LRBa, and the red narrow band light. Includes LRNb.

In the spectrum example of FIG. 17C, the illumination light is blue narrow band light LBNa, blue wide band light LBBb, first green narrow band light LGNa, second green narrow band light LGNb, red narrow band light LRNa, red wide band light. Includes LRBb.

In the spectrum example of FIG. 17D, the illumination light is blue narrow band light LBNa, blue wide band light LBBb, first green narrow band light LGNa, second green narrow band light LGNb, red wide band light LRBa, red narrow band light. Includes LRNb.

In the spectrum example of FIG. 18A, the illumination light is blue narrow band light LBNa, blue wide band light LBBb, green wide band light LGB, green narrow band light LGNb, first red narrow band light LRNa, and second red narrow band light. Includes LRNb.

In the spectrum example of FIG. 18B, the illumination light is blue broadband light LBBa, blue narrow band light LBNb, first green narrow band light LGNa, second green narrow band light LGNb, red narrow band light LRNa, red wide band light. Includes LRBb.

In the spectrum example of FIG. 18C, the illumination light is blue wideband light LBBa, blue narrowband light LBNb, first green narrowband light LGNa, second green narrowband light LGNb, red wideband light LRBa, red narrowband light. Includes LRNb.

In the spectrum example of FIG. 18D, the illumination light is the first blue broadband light LBBa, the second blue broadband light LBBb, the first green narrow band light LGNa, the second green narrow band light LGNb, and the first red narrow band light. Includes LRNa, second red narrowband light LRNb.

3. 3. Light emission timing and image processing With reference to FIG. 19, the light emission timing in the surface sequential method and image processing for the captured image will be described. In the following, a case where a color image sensor is used will be described as an example, but the present invention is not limited to this. That is, when a monochrome image sensor is used, the light in each band may be emitted in sequence. Further, although the spectrum example of FIG. 2 will be described below, the same method can be applied to any of the spectrum examples described in FIGS. 3 to 18 (D).

The light source control unit 312 emits the first red light from the light source unit 100 during the first imaging period IMT1 and emits the second red light from the light source unit 100 during the second imaging period IMT2 different from the first imaging period IMT1. In FIG. 19, the first red light is the first red broadband light LRBa, and the second red light is the second red broadband light LRBb. The second imaging period IMT2 is, for example, the next imaging period of the first imaging period IMT1. By repeating the imaging period IMT1 and IMT2, a moving image is captured.

The processing unit 310 combines the first imaging signal imaged by the imaging unit 250 during the first imaging period IMT1 and the second imaging signal imaged by the imaging unit 250 during the second imaging period IMT2 to display an image. Generates an image signal for the red channel of. The first and second imaging signals here correspond to the signals of the R channel of the captured image. For example, the processing unit 310 adds the red image obtained by the first imaging signal and the red image obtained by the second imaging signal at a predetermined ratio.

According to the present embodiment, the first red broadband light LRBa and the second red broadband light LRBb are emitted in a time-divided manner to correspond to an image corresponding to the first red broadband light LRBa and a second red broadband light LRBb. You can get the image. Then, by synthesizing these images, it is possible to perform image processing for improving the color reproducibility at the time of synthesizing the images, so that the color reproducibility can be improved.

Further, in the present embodiment, the light source control unit 312 emits the first blue light from the light source unit 100 during the first imaging period IMT1 and emits the second blue light from the light source unit 100 during the second imaging period IMT2. In FIG. 19, the first blue light is blue narrow band light LBNa, and the second blue light is blue broadband light LBBb.

The processing unit 310 combines the first imaging signal imaged by the imaging unit 250 during the first imaging period IMT1 and the second imaging signal imaged by the imaging unit 250 during the second imaging period IMT2 to display an image. Generates an image signal for the blue channel of. The first and second imaging signals here correspond to the signals of the B channel of the captured image. For example, the processing unit 310 adds the blue image obtained by the first imaging signal and the blue image obtained by the second imaging signal at a predetermined ratio.

By doing so, the blue narrow band light LBNa and the blue wide band light LBBb are emitted in a timely manner, so that an image corresponding to the blue narrow band light LBNa and an image corresponding to the blue wide band light LBBb can be acquired. Then, by synthesizing these images, it is possible to perform image processing for improving blood vessel visibility, color reproducibility, or both at the time of synthesizing, so that blood vessel visibility or color reproducibility can be performed. , Or both can be improved.

Further, in the present embodiment, the processing unit 310 performs at least one of contrast enhancement image processing, edge enhancement image processing, and blood vessel structure image processing on the first imaging signal corresponding to the blue narrow band light LBNa. Then, the processing unit 310 generates an image signal of the B channel of the display image by synthesizing the first image pickup signal after the image processing and the second image pickup signal corresponding to the blue broadband light LBBb. The first and second imaging signals here correspond to the signals of the B channel of the captured image.

In this way, image processing for emphasizing blood vessels is performed on the first imaging signal corresponding to the blue narrow band light LBNa. Thereby, the visibility of blood vessels can be further improved.

Further, in the present embodiment, the four or more lights emitted by the light source unit 100 include the first blue light, the second blue light, the green light, and the red light. The light source control unit 312 emits the first blue light from the light source unit 100 during the first imaging period IMT1 and emits the second blue light from the light source unit 100 during the second imaging period IMT2. In FIG. 19, the first blue light is blue narrow band light LBNa, the second blue light is blue broadband light LBBb, green light is green broadband light LGB, and red light is first red wide band light LRBa or first. 2 Red broadband light LRBb. In FIG. 19, the light source control unit 312 emits green light from the light source unit 100 during the first imaging period IMT1 and emits red light from the light source unit 100 during the first imaging period IMT1 or the second imaging period IMT2. However, the imaging period in which green light and red light are emitted is not limited to this, and may be arbitrary.

The processing unit 310 performs a first gain process on the first imaging signal imaged by the imaging unit 250 during the first imaging period IMT1 and the second imaging signal imaged by the imaging unit 250 during the second imaging period IMT2. Then, the image signal of the blue channel of the display image is generated by synthesizing the first imaging signal and the second imaging signal after the first gain processing. The first and second imaging signals here correspond to the signals of the B channel of the captured image. For example, the first gain process is a process of multiplying the first imaging signal by the first gain and multiplying the second imaging signal by the second gain. Alternatively, the first gain process is a process of multiplying the first image pickup signal or the second image pickup signal by a predetermined gain.

Further, the processing unit 310 generates an image signal of the green channel of the display image based on the third image pickup signal imaged by the image pickup unit 250 during the image pickup period IMT1 in which the green light is emitted from the light source unit 100. The third imaging signal corresponds to the G channel of the imaging signal.

Further, the processing unit 310 generates an image signal of the red channel of the display image based on the fourth image pickup signal imaged by the image pickup unit 250 during the image pickup period (IMT1 or IMT2) when the red light is emitted from the light source unit 100. The fourth imaging signal corresponds to the R channel of the imaging signal.

Then, the processing unit 310 performs the second gain processing on the blue channel image signal, the green channel image signal, and the red channel image signal of the display image, and the blue channel image signal after the second gain processing. And the image signal of the green channel and the image signal of the blue channel are combined to generate a display image. For example, the second gain process is a process of multiplying the blue channel image signal by the third gain, multiplying the green channel image signal by the fourth gain, and multiplying the red channel image signal by the fifth gain.

By doing so, it is possible to perform a compositing process for adjusting the color reproducibility in each of the blue region and the red region, and further adjust the color balance at the time of RGB compositing. As a result, the color reproducibility in each color region and the color balance in the white light image can be improved, and the color reproducibility can be improved.

The endoscope device of the present embodiment may be configured as follows. That is, the endoscope device of the present embodiment includes a memory for storing information and a processor that operates based on the information stored in the memory. The information is, for example, a program and various data. The processor includes hardware. The processor executes a process performed by the processing unit 310, a process performed by the light source control unit 312, or a process performed by the processing unit 310 and the light source control unit 312.

In the processor, for example, the functions of each part may be realized by individual hardware, or the functions of each part may be realized by integrated hardware. For example, a processor includes hardware, which hardware can include at least one of a circuit that processes a digital signal and a circuit that processes an analog signal. For example, a processor can be composed of one or more circuit devices mounted on a circuit board or one or more circuit elements. One or more circuit devices are, for example, ICs and the like. One or more circuit elements are, for example, resistors, capacitors, and the like. The processor may be, for example, a CPU (Central Processing Unit). However, the processor is not limited to the CPU, and various processors such as GPU (Graphics Processing Unit) or DSP (Digital Signal Processor) can be used. Further, the processor may be an integrated circuit device such as an ASIC (Application Specific Integrated Circuit) or an FPGA (Field Programmable Gate Array). Further, the processor may include an amplifier circuit, a filter circuit, and the like for processing an analog signal. The memory may be a semiconductor memory such as SRAM or DRAM, may be a register, may be a magnetic storage device such as a hard disk device, or may be an optical storage device such as an optical disk device. You may. For example, the memory stores instructions that can be read by a computer, and when the instructions are executed by the processor, the functions of the processing unit 310 or the light source control unit 312 are realized as processing. The instruction here may be an instruction of an instruction set constituting a program, or an instruction instructing an operation to a hardware circuit of a processor.

Although the embodiments to which the present invention is applied and the modified examples thereof have been described above, the present invention is not limited to the respective embodiments and the modified examples as they are, and at the embodiment, the gist of the invention is not deviated. The components can be transformed and embodied with. In addition, various inventions can be formed by appropriately combining a plurality of components disclosed in the above-described embodiments and modifications. For example, some components may be deleted from all the components described in each embodiment or modification. Further, the components described in different embodiments and modifications may be combined as appropriate. In this way, various modifications and applications are possible within a range that does not deviate from the gist of the invention. In addition, a term described at least once in the specification or drawing together with a different term having a broader meaning or a synonym may be replaced with the different term at any part of the specification or drawing.

10 Endoscope device, 100 light source unit, 105 light source device for endoscope, 110 light source drive unit, 120 optical confluence unit, 200 scope, 210 light guide, 220 illumination lens, 250 image pickup unit, 310 processing unit, 312 light source control Unit, 314 control unit, 400 display unit, 500 operation unit, ASB second mucosal color reproduction wavelength region, CRB first mucosal color reproduction wavelength region, GA green region, HBC hemoglobin light absorption spectrum, HWA to HWC vascular emphasis wavelength region , ILM illumination light, IMT1 first imaging period, IMT2 second imaging period, LBBa first blue broadband light, LBBb second blue broadband light, LBNa first blue narrow band light, LBNb second blue narrow band light, LGB green broadband Light, LGNa 1st green narrow band light, LGNb 2nd green narrow band light, LRBa 1st red wide band light, LRBb 2nd red wide band light, LRNa 1st red narrow band light, LRNb 2nd red narrow band light, LSA ~ LSF light source, PKA-PKC peak, RA red region

Claims

A light source unit having four or more light sources that emit four or more lights having different peak wavelengths from each other.
A light source control unit that can independently adjust the amount of light emitted by each of the four or more light sources.
Including
The four or more lights include three lights having peak wavelengths in each of the blue region, the green region, and the red region constituting the visible light region.
The four or more light sources include a narrow-band light source that generates narrow-band light having a peak wavelength in the blood vessel-enhanced wavelength region, and a wide-band light source that generates wide-band light having a peak wavelength in a wavelength region other than the blood vessel-enhanced wavelength region. Including
A light source device for an endoscope, wherein the blood vessel-enhanced wavelength region is a wavelength region having a half-value width centered on a peak wavelength in a predetermined color region of a light absorption spectrum of hemoglobin.
In claim 1,
The missing wavelength region between the wavelength region of the narrow band light and the wavelength region of the broadband light, which includes the peak wavelength in the same color region, is narrower than the width of the wavelength region of the broadband light. Light source device for mirrors.
In claim 1 or 2,
The four or more lights are blue narrow-band light having a peak wavelength in the blood vessel-enhanced wavelength region in the blue region, green broadband light having a peak wavelength in the green region, and red broadband light having a peak wavelength in the red region. A light source device for an endoscope, which comprises light.
In any one of claims 1 to 3,
The 4 or more lights include a first red broadband light having a peak wavelength in the first mucosal color reproduction wavelength region.
The first mucosal color reproduction wavelength region is the light absorption between the minimum value and the first peak counted on the wavelength side shorter than the minimum value in the light absorption spectrum of the hemoglobin in the red region. A light source device for an endoscope, characterized in that the spectrum is in a wavelength region in which the spectrum changes sharply.
In claim 4,
The 4 or more lights include a second red broadband light having a peak wavelength in the second mucosal color reproduction wavelength region.
The second mucous membrane color reproduction wavelength region is on the longer wavelength side than the first mucous membrane color reproduction wavelength region, and is characterized in that the light absorption of hemoglobin is smaller than that of the first mucous membrane color reproduction wavelength region. Light source device for endoscopes.
In any of claims 1 to 5,
The 4 or more lights include blue broadband light having a peak wavelength in the third mucosal color reproduction wavelength region.
The third mucosal color reproduction wavelength region is a wavelength region in which the light absorption of hemoglobin is smaller than that in the blood vessel-enhanced wavelength region in the blue region, which is a light source device for an endoscope.
In any of claims 1 to 5,
The light source device for an endoscope, wherein the four or more lights include green narrow-band light having a peak wavelength in the blood vessel-enhanced wavelength region in the green region.
In claim 1 or 2,
The four or more light sources include a blue narrow band light source, a blue wide band light source, a green wide band light source, and a red wide band light source.
The green broadband light source emits green broadband light having a peak wavelength in the green region.
The blue narrow band light source emits blue narrow band light having a peak wavelength in the blood vessel emphasized wavelength region in the blue region.
The red broadband light source emits a first red broadband light having a peak wavelength in the first mucosal color reproduction wavelength region or a second red broadband light having a peak wavelength in the second mucosal color reproduction wavelength region.
The first mucosal color reproduction wavelength region is the light absorption between the minimum value and the first peak counted on the shorter wavelength side than the minimum value in the light absorption spectrum of the hemoglobin in the red region. It is a wavelength region where the spectrum changes sharply.
The second mucosal color reproduction wavelength region is a wavelength region on the longer wavelength side than the first mucosal color reproduction wavelength region, and the light absorption of hemoglobin is smaller than that of the first mucosal color reproduction wavelength region.
The blue broadband light source emits blue broadband light having a peak wavelength in the third mucosal color reproduction wavelength region.
The third mucosal color reproduction wavelength region is a wavelength region in which the light absorption of hemoglobin is smaller than that in the blood vessel-enhanced wavelength region in the blue region, which is a light source device for an endoscope.
In claim 1 or 2,
The four or more light sources include a blue narrow band light source, a blue wide band light source, a green wide band light source, a first red wide band light source, and a second red wide band light source.
The green broadband light source emits green broadband light having a peak wavelength in the green region.
The blue narrow band light source emits blue narrow band light having a peak wavelength in the blood vessel emphasized wavelength region in the blue region.
The first red broadband light source emits first red broadband light having a peak wavelength in the first mucosal color reproduction wavelength region.
The first mucosal color reproduction wavelength region is the light absorption between the minimum value and the first peak counted on the shorter wavelength side than the minimum value in the light absorption spectrum of the hemoglobin in the red region. It is a wavelength region where the spectrum changes sharply.
The second red broadband light source emits second red broadband light having a peak wavelength in the second mucosal color reproduction wavelength region.
The second mucosal color reproduction wavelength region is a wavelength region on the longer wavelength side than the first mucosal color reproduction wavelength region, and the light absorption of hemoglobin is smaller than that of the first mucosal color reproduction wavelength region.
The blue broadband light source emits blue broadband light having a peak wavelength in the third mucosal color reproduction wavelength region.
The third mucosal color reproduction wavelength region is a wavelength region in which the light absorption of hemoglobin is smaller than that in the blood vessel-enhanced wavelength region in the blue region, which is a light source device for an endoscope.
In claim 9.
The four or more light sources further include a green narrow band light source.
The green narrow band light source is a light source device for an endoscope, which emits green narrow band light having a peak wavelength in the blood vessel emphasized wavelength region in the green region.
In claim 1 or 2,
The narrow-band light is light whose half-value width of the spectrum is smaller than the half-value width centered on the peak wavelength of the light absorption spectrum of hemoglobin.
The wideband light is a light source device for an endoscope, wherein the half-value width of the spectrum is larger than the half-value width centered on the peak wavelength of the light absorption spectrum of hemoglobin.
In claim 1 or 2,
The narrow band light is light having a spectrum half width smaller than 20 nm.
The wideband light is a light source device for an endoscope, characterized in that the half width of the spectrum is larger than 20 nm.
In claim 1 or 2,
The narrow band light source is a laser diode.
A light source device for an endoscope, wherein the broadband light source is an LED, a phosphor that generates fluorescence by the light of the LED, or a phosphor that generates fluorescence by the light of a laser diode.
An endoscope device including the light source device for an endoscope according to any one of claims 1 to 13.
The light source device for an endoscope according to claim 1,
An imaging unit that images a subject illuminated by the light source unit and outputs an imaging signal.
A processing unit that generates a display image based on the image pickup signal, and
Including
The four or more lights include a first red light and a second red light having a peak wavelength in the red region.
The light source control unit emits the first red light from the light source unit during the first imaging period, and emits the second red light from the light source unit during a second imaging period different from the first imaging period.
The processing unit synthesizes the first imaging signal imaged by the imaging unit during the first imaging period and the second imaging signal imaged by the imaging unit during the second imaging period to display the display. An endoscope device characterized by generating an image signal of a red channel of an image.
The light source device for an endoscope according to claim 1,
An imaging unit that images a subject illuminated by the light source unit and outputs an imaging signal.
A processing unit that generates a display image based on the image pickup signal, and
Including
The four or more lights include a first blue light and a second blue light having a peak wavelength in the blue region.
The light source control unit emits the first blue light from the light source unit during the first imaging period, and emits the second blue light from the light source unit during a second imaging period different from the first imaging period.
The processing unit synthesizes the first imaging signal imaged by the imaging unit during the first imaging period and the second imaging signal imaged by the imaging unit during the second imaging period to display the display. An endoscope device characterized by generating an image signal of a blue channel of an image.
In claim 16,
The first blue light is blue narrow-band light having a peak wavelength in the blood vessel-enhanced wavelength region in the blue region.
The processing unit
An endoscope device characterized in that at least one of contrast-enhanced image processing, edge-enhanced image processing, and blood vessel structure image processing is performed on the first imaging signal corresponding to the blue narrow-band light.
The light source device for an endoscope according to any one of claims 1 to 13.
An imaging unit that images a subject illuminated by the light source unit and outputs an imaging signal.
A processing unit that generates a display image based on the image pickup signal, and
Including
The four or more lights include first blue light and second blue light having a peak wavelength in the blue region, green light having a peak wavelength in the green region, and red light having a peak wavelength in the red region. Including
The light source control unit emits the first blue light from the light source unit during the first imaging period, and emits the second blue light from the light source unit during a second imaging period different from the first imaging period.
The processing unit
The first gain processing is performed on the first imaging signal imaged by the imaging unit during the first imaging period and the second imaging signal imaged by the imaging unit during the second imaging period, and the first gain processing is performed. By synthesizing the first imaging signal and the second imaging signal after the gain processing, an image signal of a blue channel is generated.
An image signal of a green channel is generated based on a third imaging signal imaged by the imaging unit during the imaging period when the green light is emitted from the light source unit.
An image signal of the red channel is generated based on the fourth imaging signal imaged by the imaging unit during the imaging period when the red light is emitted from the light source unit.
The image signal of the blue channel, the image signal of the green channel, and the image signal of the red channel are subjected to the second gain processing, and the image signal of the blue channel and the green color after the second gain processing are performed. An endoscopic device characterized in that the display image is generated by synthesizing the image signal of the channel and the image signal of the red channel.