JP2014033777A - Electronic endoscope apparatus and illumination device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To appropriately adjust a light quantity without flicker in an electronic endoscope apparatus capturing an image by sequentially illuminating a plurality of types of illumination light with different spectra.SOLUTION: The electronic endoscope apparatus (10) includes: an illumination light generation unit (70) that generates a plurality of types of illumination light with different spectra; a light source control unit (72) that sequentially switches the illumination light to be applied to an observation object area and controls the light quantity of each illumination light; an imaging unit that has an imaging device (52) for imaging the observation object area to which the illumination light is applied; a weighting processing unit (62) that sets weighting for use in a calculation of the light quantity adjustment on the basis of image data captured under the illumination of illumination light according to the type of the applied illumination light; and the light quantity adjustment unit (64) that calculates alight quantity adjustment value by reflecting the weighting according to the type of the illumination light therein. The light source control unit (72) controls, based on the light quantity adjustment value, a light quantity of another type of illumination light to be applied after the illumination of the illumination light in the imaging by which the image data used for the calculation of the light quantity adjustment value is obtained.

Description

  The present invention relates to an electronic endoscope apparatus and an illumination apparatus, and more particularly to a technique for controlling the amount of illumination light in an electronic endoscope that performs imaging by sequentially irradiating a plurality of types of illumination light.

  In the field of endoscopes, a plurality of types of illumination light (lights of different spectra) having different light wavelength ranges and central wavelengths are sequentially irradiated onto the observation region, and imaging is performed under each illumination light. Thus, electronic endoscope apparatuses that acquire color images and special light images are known (Patent Documents 1 to 3).

  Moreover, in patent document 4, regarding the light amount control of illumination light, a luminance image consisting only of a luminance component (Y component) is generated from a frame image acquired by an electronic endoscope (scope), and the luminance value is equal to or greater than a predetermined threshold value. A configuration is disclosed in which the amount of irradiation light is adjusted by a microcomputer when a high-luminance pixel group is detected.

JP 2006-280465 A JP-A-2-119005 JP 2012-10981 A JP 2007-97711 A

  In the case of an endoscope system that performs imaging using a light source device that sequentially emits multiple types of illumination light, the brightness varies depending on the type of illumination light, so processing is performed with a different brightness gain for each type of illumination light. Done. Therefore, if the image signals picked up under the illumination light sequentially irradiated are used as they are for light amount adjustment (automatic exposure control) under the same conditions, there is a problem that appropriate light amount adjustment cannot be performed. is there. If the amount of illumination light sequentially irradiated is not adjusted appropriately, the brightness of the image fluctuates and the display image flickers.

  In this regard, Patent Documents 1 and 2 disclose that the emission intensity in each wavelength region of R (red), G (blue), and B (green) that are sequentially irradiated is individually controlled. The light amount adjustment is not performed in units of RGB frames acquired in step (1). In Patent Document 3, there is no disclosure of a specific control method for adjusting the light amount of each illumination light sequentially irradiated. In Patent Document 4, the light amount adjustment is actually performed only when high luminance is detected, and the light amount adjustment for each light source color of the sequentially irradiated light source is not supported.

  The present invention has been made in view of such circumstances, and an electronic endoscope apparatus and an illuminating apparatus capable of performing appropriate light amount adjustment without flickering in a configuration in which the above-described problems are solved and sequential irradiation is performed. The purpose is to provide.

  In order to achieve the above object, the following invention is provided.

  (First Aspect): An electronic endoscope apparatus according to a first aspect irradiates an observation region among an illumination light generation unit that generates a plurality of types of illumination light having different light spectra and a plurality of types of illumination light. A light source control unit that sequentially switches the illumination light and controls the amount of each illumination light, an imaging unit that has an imaging element that captures the observation region irradiated with the illumination light, and an illumination light that is applied to the observation region Depending on the type, a weight processing unit that sets a weight used for light amount adjustment calculation based on image data captured by the imaging unit under the illumination light irradiation, and a weighting according to the type of illumination light irradiated And a light amount adjustment unit that calculates a light amount adjustment value based on image data, and the light source control unit irradiates illumination light at the time of imaging when the image data used to calculate the light amount adjustment value is obtained. Another type of illumination later It is controlled on the basis of the amount of light to the light quantity adjustment value.

  According to this aspect, illumination lights having different spectra are sequentially irradiated, and an observation region is imaged under each illumination light. By switching the illumination light, image data with different types of illumination light can be obtained from the imaging unit. When calculating the light intensity adjustment value of the illumination light from the acquired image data, grasp the spectrum of the image data obtained when the illumination light is irradiated, and the type of the irradiated illumination light Weighting is performed according to (spectrum), and the result is used for light amount adjustment.

  Thereby, appropriate light quantity adjustment according to the kind of illumination light is attained. According to this aspect, the illumination light quantity of another spectrum irradiated after that can be appropriately controlled using the latest image information acquired under illumination light having different spectra. Light quantity adjustment can be performed in units of image of each surface acquired under each illumination light according to sequential illumination (unit of frame image corresponding to each illumination light). High nature.

  (Second Aspect): The electronic endoscope apparatus according to the first aspect may include a storage unit that stores data defining the relationship between the type of illumination light and the weight.

  It is preferable to set weighting in consideration of the degree of influence on automatic exposure control for each type of illumination light.

  (Third Aspect): In the electronic endoscope apparatus according to the first aspect or the second aspect, the weight processing unit acquires illumination light information indicating the type of illumination light irradiated to the observation region from the light source control unit. It can be set as the structure to do.

  By providing illumination light information from the light source control unit to the weight processing unit, it is possible to grasp what kind of illumination light the image data is obtained.

  (Fourth aspect): In the electronic endoscope device according to any one of the first to third aspects, the illumination light is irradiated based on the type of the illumination light irradiated to the observation region. And a selection unit that selects whether or not the image data captured by the imaging unit is used for light amount adjustment.

  According to this aspect, it is possible to perform processing in which image data obtained when specific illumination light is irradiated among a plurality of types of illumination light is not applied to the light amount adjustment calculation.

  (Fifth Aspect): In the electronic endoscope device according to any one of the first aspect to the fourth aspect, the illumination light generation unit may include a plurality of light emission sources having different emission spectra. .

  By controlling the light emission timing and light emission intensity of a plurality of light sources, it is possible to generate illumination light with various spectra.

  (Sixth aspect): In the electronic endoscope device according to any one of the first aspect to the fifth aspect, the illumination light generation unit includes at least one light source and a wavelength component of light emitted from the light source. A wavelength limiting member that generates light having a spectrum different from the spectrum of the light emission source by performing at least one of transmission and reflection while limiting a part of the light source can be configured.

  According to this aspect, it is possible to generate illumination light having various spectra depending on whether or not the wavelength limiting member is used and the number of types of wavelength limiting members.

  (Seventh aspect): In the electronic endoscope device according to any one of the first aspect to the sixth aspect, the illumination light generation unit includes at least red (R) and green (G) as a plurality of types of illumination light. ) And blue (B) wavelength illumination light can be generated, and a plurality of types of illumination light including R, G, and B illumination light can be sequentially irradiated.

  According to this aspect, a color image can be generated by combining the R image, the G image, and the B image.

  (Eighth aspect): In the electronic endoscope device according to any one of the first to seventh aspects, the illumination light generation unit includes a white light source that generates white light and a wavelength band of white light. And a special light source that generates special light having a specific wavelength band in a narrow band.

  According to this aspect, white light (normal light) observation and special light observation are possible. It is also possible to generate a composite image obtained by combining the white light observation image and the special light observation image.

  (Ninth aspect): In the electronic endoscope device according to any one of the first to eighth aspects, the illumination light generation unit may include a laser light source.

  A laser light source is preferably used as a means for obtaining narrow band special light. Laser light sources include pulse width modulation (PWM) control, pulse number modulation (PNM) control, pulse amplitude modulation (PAM) control, and pulse density modulation (PDM). The amount of light emission can be controlled by control or other modulation methods.

  (Tenth aspect): Image processing for generating an observation image of a region to be observed from image data acquired via an imaging unit in the electronic endoscope device according to any one of the first to ninth aspects. And a display unit that displays the observation image generated by the image processing unit.

  (Eleventh aspect): In the electronic endoscope apparatus according to any one of the first aspect to the tenth aspect, a plurality of images that are captured under each illumination light by irradiating illumination light having different spectra. An image processing unit that synthesizes frame images and generates an observation image for display reproduction can be provided.

  (12th aspect): The illuminating device which concerns on a 12th aspect is the illumination light generation part which generates the multiple types of illumination light from which the spectrum of light differs, and the illumination light which irradiates to an observation area | region among multiple types of illumination light A light source control unit that sequentially switches and controls the light amount of each illumination light, a weight processing unit that sets a weight used for light amount adjustment calculation according to the type of illumination light irradiated on the observation area, and illumination light irradiation An image data acquisition unit that captures image data obtained by imaging the observed region, and a light amount adjustment unit that calculates a light amount adjustment value based on the image data by reflecting weighting, the light source control unit Based on the light amount adjustment value, the light amount of another type of illumination light irradiated after irradiation of the illumination light at the time of imaging from which the image data used for calculating the light amount adjustment value is obtained is controlled.

  In the illuminating device of the twelfth aspect, an aspect in which the same features as those described in the second aspect to the eleventh aspect are appropriately combined is possible.

  ADVANTAGE OF THE INVENTION According to this invention, in the structure which irradiates several types of illumination light from which a spectrum differs sequentially, it becomes possible to perform appropriate light quantity adjustment without flicker.

1 is an external view showing a system configuration example of an electronic endoscope apparatus according to an embodiment of the present invention. Front view showing the tip of the electronic endoscope The block block diagram which shows the principal part of the electronic endoscope apparatus Block configuration diagram showing another configuration example (configuration example 1) regarding the illumination light generation unit of the electronic endoscope apparatus Graph showing emission spectrum after wavelength conversion of violet laser light from violet laser light source, blue laser light from blue laser light source and blue laser light by phosphor Explanatory drawing schematically showing blood vessels on the surface of mucous membrane of living tissue Explanatory drawing which shows the example of a schematic display of the observation image by an endoscope apparatus Block configuration diagram showing another configuration example (configuration example 2) related to the illumination light generation unit of the electronic endoscope apparatus Block configuration diagram showing another configuration example (configuration example 3) of the illumination light generation unit of the electronic endoscope apparatus The chart which shows the irradiation timing of the special light from R, G, B light and LED Chart showing another example of irradiation timing of special light from R, G, B light and LED Block configuration diagram showing another configuration example (configuration example 4) regarding the illumination light generation unit of the electronic endoscope apparatus

  Hereinafter, embodiments of the present invention will be described in detail with reference to the accompanying drawings.

  FIG. 1 is an external view showing a system configuration example of an electronic endoscope apparatus according to an embodiment of the present invention. The electronic endoscope apparatus 10 according to the present embodiment includes a main body of the electronic endoscope 12, a processor device 14, and a light source device 16. The processor device 14 is connected to the light source device 16 and functions together as a control device 18 of the electronic endoscope 12 in cooperation with each other.

  The electronic endoscope 12 is connected to a flexible insertion portion 20 that is inserted into a body cavity of a subject (patient), an operation portion 22 that is connected to a proximal end portion of the insertion portion 20, and an operation portion 22. And a flexible portion 24 connected to the control device 18. The flexible portion 24 includes connector portions 36 and 37 that detachably connect the electronic endoscope 12 to the processor device 14 and the light source device 16.

  Although not shown, the electronic endoscope 12 is provided with various channels such as a forceps channel for inserting a tissue collection treatment instrument and the like, a channel for air supply / water supply, and the like.

  The insertion portion 20 includes a distal end portion 26 (hereinafter also referred to as “endoscope distal end portion”), a bending portion 28, and a flexible insertion portion side flexible portion 29. The distal end surface 26a of the distal end portion 26 is provided with an illumination window (see reference numeral 42 in FIG. 2) serving as an illumination light irradiation port for irradiating light to the observation region. Further, the distal end portion 26 incorporates an image pickup device (see reference numeral 52 in FIG. 3) that acquires image information of the observation region.

  The bending portion 28 is provided between the distal end portion 26 and the insertion portion side flexible portion 29, and can be bent by a turning operation of an angle knob 30 disposed in the operation portion 22, an actuator operation, or the like. . The bending portion 28 can be bent in an arbitrary direction and an arbitrary angle depending on a part of the subject in which the electronic endoscope 12 is used, and the observation direction of the illumination window 42 and the imaging element 52 of the distal end portion 26 can be changed. , Can be directed to a desired observation site.

  The operation unit 22 has an air / water supply button 32 and a forceps port 34 in addition to the angle knob 30. A flexible portion 24 that connects the operation portion 22 and the control device 18 accommodates a signal line (not shown), a light guide (LG), and the like. One end of the soft part 24 (hereinafter referred to as LG soft part) is connected to the operation part 22, and the other end is connected to the connector part 36. The connector part 36 is a composite type including a cable such as a signal line and a power supply line (not shown), a light guide for guiding illumination light, an air / water supply conduit, etc. The electronic endoscope 12 includes the connector part 36. Is connected to the processor unit 14. Further, another connector portion 37 branched from the connector portion 36 is connected to the light source device 16.

  The processor device 14 supplies power to the electronic endoscope 12 via a cable (not shown) housed in the LG flexible portion 24, controls the drive of the image sensor 52, and is acquired via the image sensor 52. An image pickup signal is received, and various kinds of signal processing are performed on the received image pickup signal to convert it into desired image data. A display device 38 (corresponding to a “display unit”) is connected to the processor device 14, and image data generated by the processor device 14 is displayed on the display device 38 as an endoscopic image (display image). . Further, the processor device 14 functions as a control unit that comprehensively controls the entire system of the electronic endoscope device 10.

  The light source device 16 is a means for generating illumination light. The light source device 16 of this example can generate a plurality of types of illumination light having different spectra (distribution of wavelength components) and cooperates with the processor device 14. The type of illumination light and the amount of irradiation light can be controlled. In addition, the light source device 16 of this example includes an air / water supply device.

  FIG. 2 is a front view showing the distal end portion 26 of the electronic endoscope 12. As shown in FIG. 2, an observation window 40, an illumination window 42, a forceps outlet 44, and an air / water supply nozzle 46 are provided on the distal end surface 26 a of the endoscope distal end portion 26. The observation window 40 is provided with an imaging optical system (an imaging unit including the objective lens unit 50 and the imaging element 52 in FIG. 3) behind it, and observation of the observation target (imaging of the observation region) is performed through the observation window 40. Done. The observation window 40 is disposed at the center on one side of the distal end surface 26a (the upper central portion in the upper semicircle on the circular distal end surface 26a shown in FIG. 2).

  Two illumination windows 42 are arranged at symmetrical positions with respect to the observation window 40. In FIG. 2, an illumination window 42 is provided at a symmetrical position across the observation window 40. The light generated by the light source device 16 (see FIG. 1) is guided to the illumination window 42 at the distal end portion of the endoscope through the light guide (reference numeral 76 in FIG. 3) in the electronic endoscope 12, and from the illumination window 42 to the body cavity. Illumination light is irradiated to the site to be observed. While illuminating the observation site from the illumination window 42, the imaging element 52 images the observation site (observation region) through the observation window 40.

  The forceps outlet 44 is connected to a forceps channel (not shown) disposed in the insertion portion 20 and communicates with a forceps port 34 (see FIG. 1) provided in the operation portion 22. Various types of treatment tools having an injection needle, a high-frequency knife or the like disposed at the tip are inserted into the forceps port 34, and the tips of the various types of treatment tools are exposed from the forceps outlet 44. The air supply / water supply nozzle 46 supplies the cleaning water and air supplied from the air supply / water supply device according to the operation of the air supply / water supply button 32 (see FIG. 1) provided in the operation unit 22. And can be injected into the body cavity.

  FIG. 3 is a block diagram showing the main part of the electronic endoscope apparatus 10. An objective lens unit 50 is attached to the distal end portion 26 (see FIG. 1) of the electronic endoscope 12, and an imaging element 52 is disposed behind the objective lens unit 50. The objective lens unit 50 has a zoom function for controlling the focal length and an autofocus function for focusing on the subject.

  A device such as a CMOS (Complementary Metal-Oxide Semiconductor) image sensor or a CCD (Charge Coupled Device) image sensor can be used for the image sensor 52. The imaging element 52 can be a monochrome imaging element (a configuration that does not include a color separation color filter). Instead of a monochrome image sensor, primary color image sensors having sensitivity to the basic colors of red (R), green (G), and blue (B) (for example, R, G, and B primary color color filters are used). A method of photoelectrically converting color-separated light) can be used. Further, the color-separated light is photoelectrically converted through a complementary color image sensor having sensitivity to basic colors of cyan (C), magenta (M), and yellow (Y) (for example, C, M, and Y complementary color filter). It is also possible to use a method.

  The imaging signal output from the imaging element 52 is converted into a digital signal by an analog / digital (A / D) converter 54 and transmitted to the processor device 14. It should be noted that the peripheral circuit including the A / D converter 54 and the CMOS sensor can be configured as a CMOS image pickup chip formed on the same chip.

  Although not shown in the figure, the peripheral circuit includes an analog signal processing circuit (AFE; analog front end), a parallel / serial (P / S) converter, an LVDS (Low Voltage Differential Signal) transmitter, a register, a timing generator ( TG) and the like can be included. The AFE includes a correlated double sampling (CDS) circuit, a gain setting circuit (PGA), and an A / D converter 54.

  The CDS circuit performs correlated double sampling processing on an imaging signal composed of pixel signals sequentially read from each pixel of the CMOS sensor, and removes reset noise and amplifier noise generated in the CMOS sensor. The PGA amplifies the image signal from which noise has been removed by the CDS circuit with a gain (amplification factor) designated by the processor device 14.

  The A / D converter 54 converts the imaging signal (analog imaging signal) amplified by the PGA into a digital signal having a predetermined number of bits and outputs the digital signal. An imaging signal (digital imaging signal) digitized and output by the A / D converter 54 is converted from a parallel signal to a serial signal, and sent to the processor device 14 by an LVDS (Low Voltage Differential Signal) transmission method.

  The processor device 14 includes an image processing unit 60, a weight processing unit 62, and a light amount adjustment unit 64. In this example, the image processing unit 60 is constituted by a digital signal processor (DSP), and the weight processing unit 62 and the light amount adjusting unit 64 are software (CPU: central processing unit) 66 executed by a software ( Program). However, the specific configuration for realizing these units (60, 62, 64) may have various modes. For example, these units (60, 62, 64) may be realized by a circuit such as a DSP, an FPGA (Field Programmable Gate Array), or an ASIC (Application Specific Integrated Circuit), or may be realized by software executed by the CPU 66. It may be realized by an appropriate combination of these.

  Image data (hereinafter referred to as “RAW image data”) transmitted from the electronic endoscope 12 to the processor device 14 through the connector unit 37 is input to the image processing unit 60. This RAW image data is unprocessed (raw) image data in which the image development signal obtained from the image sensor 52 is not subjected to digital development processing for so-called picture creation.

  The image processing unit 60 performs signal processing such as color interpolation, color separation, gain correction, color balance adjustment, gamma correction, and image enhancement processing on the input RAW image data to generate image data for display reproduction. To do. The image processing unit 60 has a composite processing function for generating one or a plurality of composite images by combining a plurality of frame images obtained by irradiating illumination light having different spectra.

  The image data generated by the image processing unit 60 is converted into a video signal having a signal format corresponding to the display device 38 and output to the display device 38. Thus, the image information acquired through the image sensor 52 of the electronic endoscope 12 is displayed on the display device 38 as an endoscope observation image. Moreover, the data of the endoscopic observation image generated by the image processing unit 60 is stored in a storage unit (reference numeral 68 or not shown) such as a memory or a storage device as necessary.

  The means for storing the data of the endoscopic observation image may be a storage device (memory, hard disk, etc.) built in the processor device 14 or an external storage device that can be attached to and detached from the processor device 14. Alternatively, it may be an external device connected to the processor device 14 via a wired or wireless communication interface.

  In addition, an input device such as a keyboard, a mouse, and a touch panel is connected to the processor device 14, and various input operations can be performed from the input device by a graphical user interface (GUI) using the display of the display device 38. .

  The light source device 16 is capable of generating a plurality of types of illumination light having different light spectra (intensity distributions of wavelength components), the type of illumination light emitted from the illumination light generation unit 70, and the amount of the illumination light. A light source controller 72 for controlling the light source. The light source control unit 72 can be mounted in the processor device 14, and the CPU 66 of the processor device 14 can also serve as the light source control unit 72.

  The control device 18 combining the processor device 14 and the light source device 16 in the present embodiment corresponds to an “illumination device” as a whole.

  FIG. 3 shows a plurality of light emission sources (light source 1, light source 2,... Light source N) corresponding to the types (N types) of illumination light that can be selectively output from the illumination light generation unit 70. Reference numeral 74-k (k = 1, 2,... N) (N is an integer of 2 or more). However, the configuration of the illumination light generator 70 is not necessarily required to have an individual light source for each type of illumination light. For example, by selecting and outputting the light emitted from a single light source through a wavelength limiting member such as a spectral filter or a transmission wavelength band limiting filter, a plurality of types of illumination light is selected according to the characteristics of the wavelength selecting member. Can be obtained. The wavelength limiting member is not limited to the transmission type, and may be a member that limits the wavelength by reflection, and may be configured to limit the wavelength by combining reflection and transmission. That is, the wavelength limiting member generates light having a spectrum different from the original spectrum of the light source by limiting at least one of the wavelength components of the light emitted from the light source and performing at least one of transmission and reflection. If it is.

  In the case of a configuration including a plurality of light emitting sources, illumination light having a spectrum in which the wavelength components generated by the respective light emitting sources are added can be obtained by simultaneously lighting the plurality of light emitting sources. That is, various types (spectrums) of illumination light can be realized by changing the combination of light emitting sources that emit light simultaneously.

  Here, in order to simplify the description, the description will be made assuming that N types of light sources 1, light sources 2,..., Light source N corresponding to each of a plurality of types (N types) of illumination light are provided. Note that the number of types of illumination light and the spectrum of each illumination light are not particularly limited. As the light sources 1, 2,..., Light sources N, laser light sources having different emission spectra can be used.

  The illumination light emitted from the illumination light generation unit 70 enters a light guide (optical fiber) 76 and is guided through the light guide 76 to the illumination window 42 at the distal end of the insertion unit 20 of the electronic endoscope 12.

  The light source controller 72 controls the light emission timing and the amount of light emitted from each of the light sources 1 to N, and sequentially irradiates a plurality of types of illumination light having different spectra from the endoscope distal end portion 26. For example, control is performed to sequentially switch five types of illumination light of R light, G light, B light, special light 1 and special light 2 with a ring number, and R light → G light → B light → special light 1 → special light 2 → Sequential irradiation of R light (same repetition) can be performed.

  Light incident on the image sensor 52 via the objective lens unit 50 during illumination light irradiation is photoelectrically converted by the image sensor 52 and output from the image sensor 52 as an image signal. Thereby, frame sequential image data (for example, R image, G image, B image, special light 1 image, special light 2 image) corresponding to irradiation of each illumination light is obtained.

  In the processor device 14 of this example, an element that functions as an “image data acquisition unit” for capturing image data (RAW image) from the electronic endoscope 12 is a connector to which the connector unit 37 of the electronic endoscope 12 is connected. Or a signal line 84 of image data (RAW image) or an input terminal portion thereof.

  In the case of a configuration in which a plurality of types of illumination light are sequentially irradiated while switching, RAW images having different brightness for each type of illumination light are obtained. Therefore, in this embodiment, when adjusting the amount of illumination light based on the RAW image, what kind of spectrum illumination light is irradiated to the RAW image output from the image sensor 52 under sequential irradiation. The weight processing unit 62 performs weighting processing after determining whether the current RAW image is obtained, and uses the result for light amount adjustment.

  The weight processing unit 62 performs weighting used for calculation of light amount adjustment based on RAW image data captured by the image sensor 52 under the illumination light irradiation according to the type of illumination light irradiated on the observation region. Set.

  In the processing in the weight processing unit 62, a numerical value (weighting coefficient) corresponding to “weight” is determined in advance for each type of illumination light, and the type of illumination light used for irradiation at the time of RAW image acquisition is determined. The weight corresponding to the type of illumination light is determined. For example, data of a lookup table (referred to as “weight LUT”) that specifies the correspondence between the type of illumination light and the weighting factor is stored in advance in the storage unit 68 in the processor device 14. This weight is set as a value indicating the degree of influence on automatic exposure control (automatic control of illumination light quantity) for each type of illumination light having a different spectrum.

  To explain with a simple example, when image processing for generating one color image from RGB frame sequential images is performed, the luminance signal of the color image is the R signal, G signal, and B signal added together at a predetermined mixing ratio. Obtained as a product.

Y = r * R + g * G + b * B
r, g, and b represent mixing ratios, respectively. For example, r = 0.299, g = 0.588, b = 0.114, and the like.

  When the brightness of the RAW image is relatively evaluated based on the luminance index, the R light source, the B light source, and the G light source are respectively applied to the RAW image of each color acquired in R, G, and B frame sequential. The corresponding weight can be defined as the reciprocal of the corresponding RGB mixing ratio (1 / r, 1 / g, 1 / b). For special light other than RGB, the brightness corresponding to the spectrum (intensity distribution of wavelength components) of the illumination light can be evaluated in advance and set as a weight.

  In addition, the kind of light source is not specifically limited, By way of example, a laser light source with a center wavelength of 405 nm, 445 nm, or 473 nm, or a laser light source with another wavelength can be used. As the emission wavelength of each laser light source, a light having a wavelength of ± 40 nm of the center wavelength can be used, and a light having a wavelength of ± 10 nm of the center wavelength is preferably used. Further, not only a laser light source but also a light source such as a white light source and a wavelength limiting member (such as a filter) can be combined to generate light having a desired wavelength distribution (spectrum). Furthermore, by simultaneously lighting a plurality of light sources at an appropriate light quantity ratio, it is possible to obtain illumination light having a desired spectrum in which the wavelength components of the respective light sources are superimposed.

  Further, it is not always necessary to evaluate the luminance level index used for light amount adjustment with reference to the luminance (Y) signal. For example, it is possible to evaluate with reference to the G signal. The method of determining the weight in the weight processing unit 62 can be designed as appropriate in relation to the gain correction processing for correcting the brightness gain in the subsequent image processing unit 60. It is preferable that a weight corresponding to each illumination light is determined in accordance with an index used for determining the brightness level in the image processing unit 60.

  The light source control unit 72 notifies the weight processing unit 62 of illumination light information that identifies the type of illumination light used for irradiation. Based on the illumination light information provided from the light source controller 72, the weight processing unit 62 refers to the weight LUT, determines a weight corresponding to the type of illumination light related to the RAW image, and uses the weight. Weight processing is performed on the RAW image data. For example, an operation for multiplying the RAW image data by a weight is performed.

  The light amount adjustment unit 64 calculates the light amount adjustment value of the illumination light based on the RAW image data in which the weight according to the type of the illumination light is taken into consideration through the processing by the weight processing unit 62. For example, an index value (referred to as “brightness evaluation value”) representing the brightness of the RAW image, such as an integrated value or an average value of all the pixels of the RAW image, or an integrated value or an average value of a part of the pixel area in the RAW image. ) And the light amount adjustment value of the illumination light is determined based on the brightness evaluation value.

  A look-up table (referred to as “light amount adjustment LUT”) that defines the relationship between the brightness evaluation value indicating the brightness of the RAW image and the light amount adjustment value is stored in advance in the storage unit 68 in the processor unit 14. The light amount adjustment value can be determined by referring to the light amount adjustment LUT.

  Alternatively, a correction value (correction coefficient) for matching the calculated brightness evaluation value with a predetermined specified value (target value) can be calculated, and the correction value can be used as the light amount adjustment value.

  Information calculated by the light amount adjustment unit 64 is sent to the light source control unit 72. The light source control unit 72 generates a light amount control signal based on the light amount adjustment value notified from the light amount adjustment unit 64, and controls the light amount of illumination light used for the next irradiation by the light amount control signal. The light source control unit 72 of the present example uses the light amount adjustment value to determine the light amount of another type of illumination light that is emitted after the illumination light is irradiated at the time of imaging from which the image data used to calculate the light amount adjustment value is obtained. Control.

  Means for increasing or decreasing the amount of illumination light include pulse width control (PWM), pulse number control (PNM), pulse amplitude control (PAM), pulse density control (PDM), other modulation methods, and current supplied to the light source ( There is a mode for controlling the power), a mode for controlling the diaphragm for changing the amount of light passing through, or a mode for combining these modes.

  The light source controller 72 controls each light source 74-k (k = 1, 2,... N) of the illumination light generator 70 to control the amount of light (for example, a control value for PWM control, PNM control). A control value for PAM, a control value for PAM control, a control value for PDM control, a control signal for control using other modulation methods, or a combination of signals, etc.).

  In this way, the calculation of the light amount adjustment described above is performed for each RAW image acquired in the surface sequence by sequential irradiation (in units of one frame of the RAW image), and is reflected in the control of the illumination light used for the next irradiation. That is, it is possible to control the amount of illumination light of the next frame (a frame acquired by illuminating illumination light with a different spectrum) using the latest frame brightness information in the sequential illumination cycle.

  According to the present embodiment, illumination light having different spectra is irradiated while being sequentially switched, and one frame of sequential irradiation is performed based on each image data (RAW image) that is sequentially captured under irradiation with different illumination light. The amount of illumination light is controlled in units. Based on the brightness information of the RAW image acquired immediately before (or most recently), the illumination light when acquiring the next frame image can be controlled.

  A mode in which the amount of illumination light of the next frame is controlled based on the RAW image relating to the immediately preceding frame is preferable. However, it is not always necessary to reflect the information of the immediately preceding frame in the light amount control of the next frame. For example, in the present embodiment, for a specific illumination light, it is possible to select that image data captured at the time of irradiation of the illumination light is not used for light amount adjustment. That is, depending on the type of illumination light used, an aspect in which image data acquired at the time of illumination light irradiation is not used for light amount adjustment is also possible.

  In this case, the light amount adjustment value calculated from the RAW image of the immediately preceding frame may not necessarily be applied, but the image information of the latest frame that can be used for light amount adjustment is used.

  A configuration that can select whether or not to use image data captured under the illumination light for light amount adjustment according to the type of illumination light that has been irradiated is, for example, automatically for a specific type of illumination light that has been programmed in advance. In other words, it can be excluded from the use of light amount adjustment.

  In this case, the weight processing unit 62 determines whether or not to use the RAW image data for the light amount adjustment based on the illumination light information notified from the light source control unit 72, and selects the RAW image data to be used for the light amount adjustment. Process. Then, the weighting process is performed on the one that is determined (selected) to be used for light amount adjustment. In addition, by setting the weight value when not used for light amount adjustment to a specific value such as “0”, it is possible to use it as a value that is not used for light amount adjustment in calculation.

  As described above, in the aspect of automatically selecting whether or not to use the light amount adjustment based on the irradiated color, the weight processing unit 62 and the light source control unit 72 that realize such an automatic selection function, or these The combination includes a function corresponding to the “selection unit”.

  Further, in the configuration in which it is possible to select whether or not to use the light amount adjustment based on the type of illumination light irradiated, the operator (user) selects and designates a specific type of illumination light by operating the input device 39. It is also possible to adopt an aspect. With respect to specific illumination light set by an operator's operation, image data captured under the illumination light can be configured not to be used for light amount adjustment. In this case, a user interface realized by using the input device 39 and the display device 38 that enable such an operator's selection operation, and a program that operates according to the setting correspond to the “selection unit”.

  The function sharing between the weight processing unit 62 and the light amount adjusting unit 64 is not limited to the above-described example. A light amount adjustment value (before weight processing) is calculated from RAW image data before performing weight processing, not limited to a mode in which the light amount adjustment value is calculated based on data subjected to weight processing according to the type of illumination light, A weight calculation may be performed on the light amount adjustment value (before weight processing) to obtain a light amount adjustment value (after weight processing) in consideration of the weight. That is, the weight processing unit 62 can perform a process for determining a weight, and the light amount adjustment unit 64 can perform a calculation process using the determined weight.

  According to the present embodiment, when adjusting automatic exposure based on a RAW image in imaging using a sequentially irradiated light source, the degree of influence on automatic exposure control is set for each type of illumination light (spectrum). It is possible to perform an appropriate light amount adjustment without flickering on the light.

  According to this embodiment, even when the brightness level of the RAW image is different for each type of illumination light and the brightness gain is corrected by the subsequent image processing unit 60, stable light amount adjustment without flickering is performed. It can be carried out.

<Other structural examples of the illumination light generator>
Next, another configuration example of the illumination light generator will be described.

(Configuration example 1)
FIG. 4 is a block diagram showing another configuration example of the electronic endoscope apparatus. In FIG. 4, the same or similar elements as those described in FIGS. 1 to 3 are denoted by the same reference numerals, and the description thereof is omitted. In FIG. 4, the configuration related to the processor device 14 is not shown.

  The light source device 16A illustrated in FIG. 4 includes a blue laser light source (first light source) 112 having a central wavelength of 445 nm and a violet laser light source (second light source) 114 having a central wavelength of 405 nm as light emission sources. Light emission from the semiconductor light emitting element of each of these light sources (112, 114) is individually controlled by the light source control unit 72, and the light quantity ratio between the emitted light of the blue laser light source 112 and the emitted light of the violet laser light source 114. Is changeable. That is, the light source control unit 72 functions as a means for controlling the spectrum of illumination light.

  As the blue laser light source 112 and the violet laser light source 114, a broad area type InGaN laser diode can be used, and an InGaNAs laser diode or a GaNAs laser diode can also be used. In addition, a light-emitting body such as a light-emitting diode may be used as the light source. The emission wavelength of each laser light source can be ± 40 nm, preferably ± 10 nm, of the center wavelength.

  Laser light emitted from each of the light sources (112, 114) is input to an optical fiber by a condensing lens (not shown), and passes through a combiner 116 as a multiplexer and a coupler 118 as a demultiplexer. It is transmitted to the connector unit 36. However, the present invention is not limited to this, and a configuration in which laser light from each light source (112, 114) is directly sent to the connector unit 36 without using the combiner 116 and the coupler 118 may be used.

  The laser light supplied to the connector portion 36 is propagated to the distal end portion of the electronic endoscope 12 by the light guides 76A and 76B. A phosphor 78, which is a wavelength conversion member, is disposed at the light exit ends of the light guides 76A and 76B. The blue laser light excites the phosphor 78 disposed at the light emitting end of the light guides 76A and 76B to emit fluorescence. Some of the blue laser light passes through the phosphor 78 as it is. The violet laser light is transmitted without exciting the phosphor 78 and becomes illumination light with a narrow band wavelength.

The phosphor 78 absorbs a part of blue laser light and emits a plurality of types of phosphors that emit green to yellow (for example, YAG phosphors, phosphors including BAM (BaMgAl ₁₀ O ₁₇ ), etc.). Consists of including. As a result, green to yellow excitation light using blue laser light as excitation light and blue laser light transmitted without being absorbed by the phosphor 78 are combined into white (pseudo-white) illumination light. If a semiconductor light emitting element is used as an excitation light source as in this configuration example, high intensity white light can be obtained with high luminous efficiency, and the intensity of white light can be easily adjusted. In addition, changes in the color temperature and chromaticity of white light can be kept small.

  In this configuration example, the configuration including the blue laser light source 112, the violet laser light source 114, and the phosphor 78 corresponds to the “illumination light generation unit”.

  FIG. 5 is a graph showing an emission spectrum after the wavelength conversion of the violet laser light from the violet laser light source 114, the blue laser light from the blue laser light source 112, and the blue laser light is performed by the phosphor 78. The violet laser beam is represented by a bright line (profile PF1) having a center wavelength of 405 nm. The blue laser light is represented by an emission line having a center wavelength of 445 nm, and the excitation light emitted from the phosphor 78 by the blue laser light has a spectral intensity distribution in which the emission intensity increases in a wavelength band of approximately 450 nm to 700 nm. The pseudo white light described above is formed by the profile PF2 of the excitation emission light and the blue laser light.

  The white light referred to in the present specification is not limited to one that strictly includes all wavelength components of visible light, and may be any light that includes light in a specific wavelength band such as R, G, B, for example. Light including a wavelength component from green to red, light including a wavelength component from blue to green, and the like are also included in a broad sense.

  The light source control unit 72 can relatively increase or decrease the light emission intensity of the profile PF1 and the profile PF2 to generate illumination light of an arbitrary color tone (spectrum), according to the mixing ratio of the profiles PF1 and PF2. Illumination light having different characteristics can be obtained.

  By using a laser light source, the color tone can be controlled with high resolution, the change in color tone with time is small, and the light amount can be controlled with high responsiveness. Moreover, since the luminous efficiency is high, power saving can be achieved.

  By controlling the light emission timings of the respective laser light sources (112, 114), it is possible to perform sequential irradiation in which white light → special light (purple light having a central wavelength of 405 nm) is alternately switched.

  FIG. 6 is an explanatory view schematically showing blood vessels on the surface of the mucous membrane of the living tissue. It has been reported that the surface layer of the mucosa of the living tissue is formed between the blood vessel B1 of the deep mucosa and the capillary blood vessel B2 such as a resinous vascular network to the surface of the mucosa, and the lesion of the living tissue appears in the fine structure such as the capillary blood vessel B2. Has been. Therefore, it has been attempted to detect microscopic lesions at an early stage and diagnose the lesion area by observing capillary blood vessels on the surface of the mucosa with image enhancement.

  When illumination light enters a living tissue, the incident light propagates diffusively through the living tissue, but the absorption and scattering characteristics of the living tissue have wavelength dependence, and the shorter the wavelength, the stronger the scattering characteristics. Tend. That is, the depth of light changes depending on the wavelength of illumination light. Therefore, blood vessel information from capillaries on the surface of living tissue and fine mucous patterns are obtained when the illumination light is in the wavelength region λa near 400 nm, and blood vessel information including deeper blood vessels is obtained in the wavelength region λb near 500 nm. Be able to. Therefore, a light source having a central wavelength of 360 to 800 nm, preferably 365 to 515 nm, and more preferably a central wavelength of 400 nm to 470 nm is used for blood vessel observation on the surface of the living tissue.

  FIG. 7 shows a schematic display example of an observation image by the electronic endoscope apparatus. As shown in FIG. 7, in the observation image when the illumination light is white light, a relatively deep blood vessel image of the living tissue is obtained, but the fine capillaries on the mucosal surface layer appear blurred. On the other hand, in the observation image when the illumination light includes a lot of visible short wavelength components, fine capillaries on the mucous membrane surface layer can be seen clearly. It is also possible to display a composite image obtained by superimposing these images.

(Configuration example 2)
FIG. 8 is a block diagram showing another configuration example of the electronic endoscope apparatus. In FIG. 8, the same or similar elements as those described in FIGS. 1 to 3 are denoted by the same reference numerals, and the description thereof is omitted. Further, in FIG. 8, illustration of the configuration related to the processor device 14 is omitted.

  In the configuration example shown in FIG. 8, a plurality of light emitting diodes are arranged at the distal end portion of the electronic endoscope 12. As the light emitting diode, for example, a blue light emitting diode 161, a green light emitting diode 163, and a red light emitting diode 165 are used, and each light emitting diode (161, 163, 165) is connected by a driver 167 connected to the light source control unit 72 on the light source device 16B side. ) Is controlled individually.

  According to this configuration, illumination light having an arbitrary color tone including white can be obtained by using light emitting elements of the three primary colors of light. In addition, a white light source 169 may be provided separately to increase the amount of white light, and white light may be supplied to the electronic endoscope 12. As the white light source 169 in this case, a halogen lamp, a xenon lamp, a white light emitting diode, or a light source using a combination of the laser light source (112) and the phosphor 78 described in FIG.

  In the case of the configuration example of FIG. 8, a configuration including the light source device 16 </ b> B and a plurality of light emitting diodes (161, 163, 165) corresponds to the “illumination light generation unit”.

(Configuration example 3)
FIG. 9 is a schematic configuration diagram illustrating an example of an electronic endoscope apparatus that performs frame sequential imaging. 9, elements that are the same as or similar to those described in FIGS. 1 to 3 are given the same reference numerals, and descriptions thereof are omitted. Further, in FIG. 9, the configuration regarding the processor device 14 is omitted.

  In the configuration example shown in FIG. 9, a rotating color filter plate 175 having R, G, B color filters 173 is disposed in the optical path from a white light source 171 such as a xenon lamp of the light source device 16C. The transmitted light from 173 is supplied to the electronic endoscope 12 as illumination light. In addition, an LED (Light Emitting Diode) 177 that emits visible short-wavelength narrow-band light (corresponding to “special light”) having a spectrum different from that of the light emitted from the white light source 171 is disposed at the distal end portion of the endoscope. The controller 72 controls the light emission of the LED 177. The light source control unit 72 outputs a drive signal to a drive motor (rotation drive means) 179 that rotationally drives the rotary color filter plate 175, and controls the light emission timing and light emission intensity of the LED 177 in synchronization with the operation of the drive motor 179. To do.

  In the middle of the optical path from the white light source 171 to the rotating color filter plate 175, an optical filter 181 for cutting unnecessary light such as infrared rays and an aperture unit 183 for controlling the amount of light are provided. An optical lens 185 and a light guide 76 for guiding light to the distal end of the endoscope are disposed. The light guides 76 are provided on the light source device 16 </ b> C side and the electronic endoscope 12 side, respectively, and are connected by a connector portion 36.

  The light source control unit 72 drives the drive motor 179 so that any one of the R, G, and B color filters 173 of the rotating color filter plate 175 is arranged on the optical path of the emitted light from the white light source 171. G light and B light are sequentially supplied to the light guide 76.

  FIG. 10 is a chart showing an example of irradiation timing of each illumination light by sequential irradiation. “R”, “G”, and “B” in FIG. 10 indicate light in the R wavelength range (R light), light in the G wavelength range (G light), and B that have passed through the R, G, and B color filters 173, respectively. The irradiation timing of the light in the wavelength range (B light) is shown, and “X” shows the irradiation timing of the narrow band light by the LED 177.

  As shown in FIG. 10, if the light emission timing for the LED 177 is set to an irradiation pattern that is set next to the B light irradiation, various illumination lights are emitted in the order of R light → G light → B light → narrowband light (X). Repetitively irradiated from the endoscope tip. An R light image, a G light image, a B light image, and a narrow-band light image (also referred to as a “special light image”) are sequentially captured at each timing when various illumination lights are irradiated. can get.

  In order to emphasize and observe the information on the surface layer of the living tissue, the LED 177 can be used with a center emission wavelength of 405 ± 40 nm, and more preferably with a center emission wavelength of 405 ± 10 nm.

  The R light image, the G light image, and the B light image obtained in the frame sequential manner are synchronized with the image processing unit 60 (see FIG. 3) to become a normal observation image by white light illumination. The narrow-band light image is obtained as an image in which capillary information and mucous membrane fine patterns on the surface of the living tissue are emphasized, and the light emission intensity of the LED 177 is increased / decreased by the light source control unit 72, so that The degree of emphasis on information can be changed.

  Further, the image processing unit 60 (see FIG. 3) synthesizes the obtained narrow-band light image into the normal observation image using the R light, G light, and B light, or the image using the R light and G light. By doing so, an image in which the information on the tissue surface layer is emphasized is generated.

  Thus, by changing the intensity of the narrow band light with respect to the white light (R light, G light, B light) by the light source control unit 72, the degree of emphasizing the information on the tissue surface layer can be arbitrarily adjusted, for observation purposes. An appropriate observation image can be obtained.

  The LED 177 used in the above configuration is not limited to a light emitting diode, but may be a semiconductor light emitting element such as a laser light source or a lamp that emits light of a desired wavelength. Laser light sources and LED light sources are relatively easy to adjust light emission and control pulse light emission. On the other hand, since it is difficult to adjust the amount of light emitted from a xenon light source or the like, it is preferable to adjust the amount of irradiation light using an aperture mechanism or the like.

  Moreover, the irradiation timing of each illumination light is not limited to the example of FIG. FIG. 11 is a chart showing another example of the irradiation timing of each illumination light. As shown in FIG. 11, it is good also as an irradiation pattern which performs irradiation with B light and narrow-band light (it shows with "X" in a figure) simultaneously. In this case, it is possible to sequentially obtain an R light image, a G light image, and an image of B light and narrow band light by repeating imaging of three frames by irradiation of R light, G light, B light and narrow band light. Become. The B light and the narrow band light are superimposed, and the illumination light becomes an illumination light whose color changes in accordance with the ratio of the emitted light quantity of the B light and the narrow band light, and thereby, an observation image obtained by simultaneously processing each color light The color changes. In the synchronized observation image, the information on the tissue surface layer is highlighted as the emission light amount ratio of the narrow band light is higher. Further, according to the present irradiation pattern, the number of times of imaging is smaller than that of the irradiation pattern described in FIG.

  9 to 11, the configuration including the white light source 171, the rotating color filter plate 175, the drive motor 179, and the LED 177 corresponds to the “illumination light generator”.

(Configuration example 4)
FIG. 12 is a schematic configuration diagram illustrating another configuration example of the light source device. In FIG. 12, the same or similar components as those described in FIG. 11 are denoted by the same reference numerals, and the description thereof is omitted. In FIG. 12, the illustration of the configuration related to the processor unit 14 is omitted.

  In the configuration example shown in FIG. 12, the light source device 16 </ b> D includes an LED 197 that emits a narrowband light with a visible short wavelength, separately from the white light source 171. In addition, the light source device 16D includes a half mirror 199 disposed in the middle of the optical path of light that passes through the rotating color filter plate 175B.

  The half mirror 199 emits the emitted light from the LED 197 introduced through different optical paths and the transmitted light from the rotating color filter plate 175B to the rear of the optical path with their optical axes aligned. Then, light emitted from the half mirror 199 is introduced into the light guide 76 via the condenser lens 185.

  The rotating color filter plate 175B has R, G, and B color filters 173, and has a light shielding property except for the substrate portion on which the color filters 173 are arranged. The rotating color filter plate 175B shields the emitted light 189 from the white light source 171 when in the rotational position shown in FIG. The LED 191 is driven to emit light by the light source controller 72 at the rotational position of the rotating color filter plate 175B, and emits narrowband light.

  The light source control unit 72 turns on the white light source 171 and rotationally drives the rotating color filter plate 175B by the drive motor 179, and a light-shielding substrate portion other than the color filter 173 is disposed in the optical path of the emitted light 189 from the white light source 171. When the rotation position is reached, the LED 197 is turned on.

  According to such a light source device 16D, in the irradiation patterns shown in FIGS. 10 and 11, in addition to the R light, G light, and B light from the white light source 171, the narrow band light from the LED 197 is sequentially or B light. At the same time, it can be emitted. The wavelength of the narrow band light can be set to an arbitrary wavelength corresponding to the emission wavelength of the LED 197 regardless of the white light source 171. Further, by providing an LED 197 separately from the white light source 171 and individually controlling the amount of light emitted from each light source, the degree of enhancement of the information on the tissue surface layer can be arbitrarily adjusted, and an appropriate observation image corresponding to the observation purpose can be obtained. I can get it.

  As a modification of the configuration of FIG. 12, a configuration in which a movable mirror and a mirror driving unit are employed instead of the half mirror 199 is also possible. The special light is not limited to one type, and a plurality of types of special light can be used.

  In the case of the configuration example described with reference to FIG. 12, the configuration including the white light source 171, the rotating color filter plate 175 </ b> D, the drive motor 179, and the LED 197 corresponds to the “illumination light generation unit”.

<Advantages of Embodiment>
As described above, in the present embodiment, the weight corresponding to the type of illumination light having a different brightness in the RAW image is used for automatic exposure. Thereby, light quantity control can be performed according to the image after processing the brightness gain based on the weight. For this reason, for example, even when illumination light that needs to increase the brightness gain is sequentially included in the irradiation, the amount of irradiation light does not flicker and can be stabilized. Therefore, it is possible to reproduce and display a stable endoscopic image without flicker.

  Further, since the light amount adjustment value can be calculated in units of frames acquired by sequential irradiation and fed back to the light amount control, the adjustment of the light amount is reflected at an early stage.

  Although the endoscope system and the control method thereof according to the present invention have been described in detail above, the present invention is not limited to the above-described embodiment, and various improvements and modifications can be made without departing from the gist of the present invention. Of course, you may also do. Many modifications can be made within the technical idea of the present invention by those having ordinary knowledge in the field.

  DESCRIPTION OF SYMBOLS 10 ... Electronic endoscope apparatus, 12 ... Electronic endoscope, 14 ... Processor apparatus, 16 ... Light source apparatus, 16A, 16B, 16C, 16D ... Light source apparatus, 18 ... Control apparatus (illumination apparatus), 20 ... Insertion part, DESCRIPTION OF SYMBOLS 22 ... Operation part, 26 ... Tip part, 26a ... Tip surface, 38 ... Display apparatus (display part), 36 ... Connector part, 37 ... Connector part, 40 ... Observation window, 42 ... Illumination window, 52 ... Imaging element, 60 ... Image processing unit, 62 ... Weight processing unit, 64 ... Light amount adjustment unit, 70 ... Illumination light generation unit, 72 ... Light source control unit, 76 ... Light guide, 76A, 76B ... Light guide, 78 ... Phosphor, 112 ... Blue Laser light source, 114: purple laser light source, 161: blue light emitting diode, 163: green light emitting diode, 165 ... red light emitting diode, 173 ... color filter, 177 ... LED, 179 ... drive motor, 197 LED, 199 ... half mirror

Claims (12)

An illumination light generator that generates multiple types of illumination light having different light spectra;
A light source control unit that sequentially switches illumination light to be irradiated on the observation region among the plurality of types of illumination light and controls the amount of each illumination light, and
An imaging unit having an imaging element that images the observed region irradiated with the illumination light;
A weight for setting a weight used for calculation of light amount adjustment based on image data obtained by imaging by the imaging unit under illumination of illumination light according to the type of illumination light irradiated on the observation area A processing unit;
A light amount adjustment unit that calculates a light amount adjustment value based on the image data by reflecting the weighting according to the type of illumination light applied to the observation region,
The light source control unit determines the light quantity of another type of illumination light irradiated after illumination light irradiation at the time of imaging from which the image data used for the calculation of the light quantity adjustment value is obtained based on the light quantity adjustment value. Electronic endoscope device to control.   The electronic endoscope apparatus according to claim 1, further comprising a storage unit that stores data defining a relationship between a type of illumination light and weighting.   The electronic endoscope apparatus according to claim 1, wherein the weight processing unit acquires illumination light information indicating a type of illumination light irradiated on the observation region from the light source control unit.   A selection unit configured to select whether or not to use the image data captured by the imaging unit under illumination of the illumination light based on the type of illumination light applied to the observation region for light amount adjustment; The electronic endoscope apparatus according to any one of claims 1 to 3.   The electronic endoscope apparatus according to any one of claims 1 to 4, wherein the illumination light generation unit includes a plurality of light emission sources having different emission spectra. The illumination light generator is
At least one light source;
A wavelength limiting member that generates light having a spectrum different from the spectrum of the light emission source by limiting at least one of transmission and reflection by limiting a part of the wavelength component of the light emitted from the light emission source;
An electronic endoscope apparatus according to claim 1, comprising: The illumination light generation unit can generate illumination light in each wavelength region of at least red (R), green (G), and blue (B) as the plurality of types of illumination light,
The electronic endoscope apparatus according to any one of claims 1 to 6, wherein irradiation with the plurality of types of illumination light including R, G, and B illumination lights is sequentially performed.   The said illumination light generation part is provided with the white light source which produces | generates white light, and the special light source which produces | generates the special light which has a specific wavelength band narrower than the wavelength band of the said white light. The electronic endoscope apparatus according to any one of the above.   The electronic endoscope apparatus according to claim 1, wherein the illumination light generation unit includes a laser light source. An image processing unit for generating an observation image of the observed region from image data acquired via the imaging unit;
A display unit for displaying an observation image generated by the image processing unit;
An electronic endoscope apparatus according to any one of claims 1 to 9.   11. The image processing apparatus according to claim 1, further comprising: an image processing unit configured to irradiate illumination lights having different spectra and to combine a plurality of frames of images captured under each illumination light to generate an observation image for display reproduction. The electronic endoscope apparatus according to claim 1. An illumination light generator that generates multiple types of illumination light having different light spectra;
A light source control unit that sequentially switches illumination light to be irradiated on the observation region among the plurality of types of illumination light and controls the amount of each illumination light, and
A weight processing unit for setting a weight used for calculation of light amount adjustment according to the type of illumination light irradiated to the observation area;
An image data acquisition unit that captures image data obtained by imaging the observed region irradiated with the illumination light;
A light amount adjustment unit that calculates a light amount adjustment value based on the image data by reflecting the weighting;
With
The light source control unit determines the light quantity of another type of illumination light irradiated after illumination light irradiation at the time of imaging from which the image data used for the calculation of the light quantity adjustment value is obtained based on the light quantity adjustment value. Lighting device to control.

Images