JP2018000498A - Endoscope system - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an endoscope system capable of adjusting a white balance correction value easily according to a color temperature of an illumination light.SOLUTION: An endoscope system includes a reference light source for emitting a reference light, other light sources for emitting other light whose color temperature is different from that of the reference light source, a light guide member alternatively connected to the reference light source or the other light sources, switching means for switching the light source between the reference light source and the other light sources, an image pick-up device for picking up an image of a subject and generating a color signal, a white balance correction part for correcting the white balance of the color signal, a correction value setting part for setting a white balance correction value used for the white balance correction, and a recording part in which a coefficient used for a function indicating relations between the white balance correction values of the reference light and the other light is recorded beforehand. When a new correction value used for the correction of the reference light source is set, and the light source is switched from the reference light source to the other light sources, correction values for the other light sources are calculated using the new correction value and the coefficient.SELECTED DRAWING: Figure 2

Description

  The present invention relates to an endoscope system.

  In an endoscope system, in order to appropriately reproduce the color of a subject, white balance correction is performed every time the endoscope is connected to a processor.

  In the white balance correction, the gain data value (white balance correction value) of each color signal is adjusted so that the color signal obtained from the image sensor is appropriate. In Patent Document 1, the difference between the white balance correction value (WBF) set by white balance adjustment and the white balance correction value (WBL) used at the previous operation is within a predetermined allowable range. A technique is disclosed in which it is determined whether or not there is a difference, and if this difference is outside the allowable range, an inspection of the apparatus is urged.

JP 2005-27872 A

  Patent Document 1 does not disclose switching between a plurality of light sources. On the other hand, when imaging an in-vivo subject with an endoscope, the color temperature of illumination light may be changed according to the purpose. For example, in order to observe blood vessels in the digestive tract, light having a wavelength that is easily absorbed by hemoglobin may be used as illumination light. Moreover, in order to observe a subject that vibrates at a high frequency, such as a vocal cord, there is a case in which stroboscopic illumination is applied (laryngeal stroboscope). In such a case, observation with an endoscope is performed by switching the illumination light source.

  If the color temperature of the illumination light after switching is different from the color temperature of the reference light when the illumination light source is switched, the color balance is corrected by using the white balance correction value of the illumination light before switching. There is a problem that balance is lost. In order to solve this problem, it can be considered that the white balance correction value is readjusted every time the light source of the illumination light is switched. However, adjusting the white balance correction value every time the illumination light source is switched is a cumbersome operation.

  In order to solve the above-described problem, the present invention can easily adjust the white balance correction value according to the color temperature of the illumination light after switching even when the illumination light is switched to one having a different color temperature. An object is to provide a mirror system.

A first aspect of the present invention is an endoscope system,
A reference light source that emits reference light of a predetermined color temperature;
At least one other light source that emits other light having a different color temperature from the reference light source;
A light guide member that is alternatively connected to the reference light source or the other light source, and selectively irradiates the subject with the reference light or the other light;
Switching means for switching which light of the reference light source or the other light source is irradiated to the subject;
An image sensor that captures an image of the subject and generates a color signal;
A white balance correction unit for correcting white balance of the color signal;
A correction value setting unit for setting a white balance correction value used for the white balance correction;
A recording unit in which a coefficient used for a function indicating a relationship between the white balance correction value of the reference light and the white balance correction value of the other light is recorded in advance;
When the correction value setting unit sets a new white balance correction value to be used for white balance correction of the reference light source, and the switching means switches the reference light source to the other light source, the white balance The correction unit calculates a white balance correction value of the other light source by using the new white balance correction value and the coefficient, and performs white balance correction of the other light source.

A first connection signal indicating that the light guide member is connected to the reference light source or a second connection signal indicating that the light guide member is connected to the other light source is output to the white balance correction unit. Connection detecting means for
The white balance correction unit preferably calculates a white balance correction value of the other light when the second connection signal is input.

  For example, the white balance correction unit calculates a white balance correction value of the other light using a difference value between a white balance correction value of the reference light and a white balance correction value of the other light as the coefficient. Also good.

  Alternatively, the white balance correction unit may calculate the white balance correction value of the other light using the ratio of the white balance correction value of the reference light and the white balance correction value of the other light as the coefficient. Good.

  When the color temperature of the reference light or the other light changes, the correction value setting unit newly calculates a white balance correction value of the reference light or other light after the change of the color temperature, and A coefficient used for a function indicating a relationship between the white balance correction value and the white balance correction value of the other light is newly calculated, and the coefficient recorded in the recording unit is updated to the newly calculated coefficient. It is preferable.

  According to the present invention, even when the illumination light is switched to one with a different color temperature, the white balance correction value can be easily adjusted according to the color temperature of the illumination light after switching, and the color balance of the observation image can be adjusted. Collapse can be suppressed.

1 is an external view of an endoscope system 1 of the present embodiment. 1 is a block configuration diagram illustrating a main configuration of an endoscope system 1. FIG. 1 is a block configuration diagram illustrating a main configuration of an endoscope system 1. FIG. 4 is a flowchart illustrating a method for calculating a coefficient and storing it in a memory 418. It is a block block diagram which shows the main structures of the endoscope system 1B which concerns on the modification of this embodiment. It is a flowchart which shows operation | movement of the endoscope system 1B when a light source is switched.

(Configuration of endoscope system)
Hereinafter, the endoscope system of the present embodiment will be described in detail. FIG. 1 is an external view of an endoscope system 1 according to the present embodiment, and FIGS. 2 and 3 are block configuration diagrams showing a main configuration of the endoscope system 1. The endoscope system 1 mainly includes a processor 2, a plurality of light source devices (a first light source device 3 </ b> A and a second light source device 3 </ b> B), an endoscope 4, and a display 5.

  In the present embodiment, an endoscope system having two light source devices will be described. However, the number of light source devices is not limited to two, and the present invention is applied to an endoscope system having three or more light source devices. You may apply. For example, the present invention may be applied to an endoscope system that uses a xenon light source as the first light source device, a halogen light source as the second light source device, and a strobe light source as the third light source device.

  The endoscope 4 and the display 5 are each connected to the processor 2. The first light source device 3A and the second light source device 3B are alternatively attached to the processor 2 and connected to the endoscope 4 together with the processor 2. Although the first light source device 3A, the second light source device 3B, and the processor 2 are configured separately, the processor 2 includes the first light source device 3A and the second light source device 3B. Also good.

Each of the first light source device 3A and the second light source device 3B is a device that sequentially outputs the light emitted from the light source as the irradiation light of the subject. The first light source device 3A includes a connector portion 300A, a lamp power driver 306A, a lamp 308A as a light source, a condensing lens 310A, and the like. Similarly, the second light source device 3B includes a connector unit 300B, a lamp power driver 306B, a lamp 308B as a light source, a condensing lens 310B, and the like.
The connector parts 300 </ b> A and 300 </ b> B are for connecting with the connector part 414 of the endoscope 4. Any one of the connector units 300A and 300B and the connector unit 414 are optically connected, so that either the first light source device 3A or the second light source device 3B and the endoscope 4 are optically connected. .

The lamp 308A is lit by the power supplied from the lamp power driver 306A and emits light. Similarly, the lamp 308B is lit by the power supplied from the lamp power driver 306B and emits light. High-intensity lamps such as a xenon lamp, a halogen lamp, and a metal halide lamp are suitable for the lamps 308A and 308B. Further, as the lamps 308A and 308B, LED (Light Emitting Diode) lamps can be used.
In the present embodiment, the color temperature of the emitted light differs between the lamp 308A and the lamp 308B. For example, a xenon lamp can be used as the lamp 308A, and a halogen lamp can be used as the lamp 308B.

  Note that at least one of the first light source device 3A and the second light source device 3B may be a strobe light emitting device that blinks emitted light at a predetermined cycle. For example, at least one of the lamp power drivers 306A and 306B may cause the light source to blink at a predetermined cycle.

  When the first light source device 3A is connected to the processor 2 and the endoscope 4, the emitted light radiated from the lamp 308A is collected by the condenser lens 310A, and after the light amount is adjusted by a diaphragm (not shown), The incident light enters the incident end of the light guide member 404 (see FIG. 2) of the endoscope 4 as irradiation light of the subject. On the other hand, when the second light source device 3B is connected to the processor 2 and the endoscope 4, the emitted light emitted from the lamp 308B is condensed by the condenser lens 310B, and the amount of light is adjusted by a diaphragm not shown. Thereafter, the light enters the incident end of the light guide member 404 (see FIG. 2) of the endoscope 4 as irradiation light of the subject.

  In the endoscope system 1 according to the present embodiment, the light source device (the first light source device 3A or the second light source device 3B) connected to the light guide member 404 is switched to irradiate the subject with irradiation light having different color temperatures. To do. In FIG. 2, the first light source device 3 </ b> A is connected to the light guide member 404, and in FIG. 3, the second light source device 3 </ b> B is connected to the light guide member 404.

The endoscope 4 includes an insertion unit 420, a hand operation unit 422, a light guide member 404, a connector unit 414, and the like.
As shown in FIG. 1, an insertion portion 420 is provided at one end of the endoscope 4, and a hand operation portion 422 is connected to the proximal end of the insertion portion 420. A connector portion 414 is provided at the other end of the endoscope 4, and the connector portion 414 is connected to the processor 2 and alternatively connected to the first light source device 3 </ b> A or the second light source device 3 </ b> B. The
The insertion part 420 has flexibility and is a part for insertion into the living body. A bent portion 424 is provided in the vicinity of the distal end of the insertion portion 420. The bending portion 424 bends in response to a remote operation from the hand operation unit 422. The bending mechanism of the bending portion 424 is a well-known mechanism incorporated in a general endoscope. In the bending structure, for example, the bending portion 424 is bent by pulling the operation wire in conjunction with the rotation operation of the bending operation knob provided in the hand operation portion 422. A distal end portion 402 is connected to the distal end of the bent portion 424. A solid-state imaging device (hereinafter referred to as an imaging device) 410 is provided on the distal end surface of the distal end portion 402. The direction of the distal end surface of the distal end portion 402 changes according to the bending operation of the bending portion 424 caused by the rotation operation of the bending operation knob, so that the imaging region by the image sensor 410 moves.

  The light guide member 404 is disposed over substantially the entire length of the endoscope 4 from the connector portion 414 to the distal end portion 402. The light guide member 404 is, for example, a light guide in which optical fibers are bundled, and guides irradiation light supplied from the first light source device 3 </ b> A or the second light source device 3 </ b> B to the distal end portion 402 of the endoscope 4. .

  As shown in FIGS. 2 and 3, the distal end portion 402 of the endoscope 4 includes a light distribution lens 406, an objective lens 408, an image sensor 410, and an amplifier 412. The light distribution lens 406 is disposed to face the front end surface of the light guide member 404, and illuminates the subject by diverging the irradiation light emitted from the front end surface of the light guide member 404. The objective lens 408 collects light from the subject (for example, fluorescence, phosphorescence, scattered light, reflected light, etc.) and forms an image of the subject on the light receiving surface of the image sensor 410. As the image sensor 410, for example, a CMOS (Complimentary Metal Oxide Semiconductor) image sensor is preferably used. An imaging signal obtained from the imaging element 410 is amplified by the amplifier 412 and then sequentially transmitted to the connector unit 414.

  The connector unit 414 is for electrically connecting the endoscope 4 and the processor 2 by connecting to the connector unit 200 of the processor 2. The connector unit 414 connects the light guide member 404 to either the lamp 308A or the lamp 308B by connecting to the connector unit 300A of the first light source device 3A or the connector unit 300B of the second light source device 3B. Is for. That is, the connector units 300A and 300B and the connector unit 414 are switching means for switching which light from the lamp 308A or the lamp 308B is irradiated to the subject.

  The connector unit 414 includes a signal processing unit 416 and a memory 418 (recording unit). The signal processing unit 416 supplies a drive signal to the image sensor 410 to drive the image sensor 410, converts an analog signal output from the image sensor 410 into a digital signal, and causes the processor 2 to output a video signal ( Color signal). In addition, the signal processing unit 416 accesses the memory 418 to read the unique information of the endoscope 4 and outputs it to the processor 2. The unique information of the endoscope 4 recorded in the memory 418 includes, for example, the number of pixels and sensitivity of the image sensor 410, an operable frame rate, a model number, and the like. Further, as will be described later, a coefficient of a function used for calculating a correction value is stored in the memory 418 as unique information of the endoscope 4 in advance.

The processor 2 is a device that further processes a video signal of a captured image of a subject obtained by the imaging element 410 of the endoscope 4 capturing a subject and supplies the processed video signal to the display 5.
The processor 2 is provided with a connector part 200 (see FIG. 1) for connecting to the connector part 414 of the endoscope 4. By mechanically connecting the connector part 414 and the connector part 200, the endoscope 4 and the processor 2 are electrically connected.

The processor 2 includes a memory 201, a system controller 202, an operation panel 218, a video signal processing unit 220, and the like.
The memory 201 stores various programs for controlling the operation of the entire endoscope system 1.
The system controller 202 reads and executes various programs stored in the memory 201 to control the operation of the entire endoscope system 1. Further, the system controller 202 changes various settings of the electronic endoscope system 1 in accordance with an instruction input from the operation panel 218 by the operator (observer).

  In the present embodiment, the system controller 202 functions as a connection detection unit that determines that the light guide member 404 is connected to either the first light source device 3A or the second light source device 3B. For example, when the first light source device 3A is connected to the processor 2 and the endoscope 4, the system controller 202 performs video signal processing on the first connection signal indicating that the first light source device 3A is connected. Output to the unit 220. Alternatively, the system controller 202 performs video signal processing on the second connection signal indicating that the second light source device 3B is connected when the second light source device 3B is connected to the processor 2 and the endoscope 4. Output to the unit 220.

  The video signal processing unit 220 (white balance correction unit) processes the video signal of the captured image supplied from the endoscope 4 to generate a video format signal supplied to the display 5. The video signal processing unit 220 performs known signal processing such as gamma correction on the video signal transmitted from the signal processing unit 416 in addition to white balance correction. The video signal processing unit 220 includes a main calculation unit 222, a correction value setting unit 224, and the like. Hereinafter, the white balance correction will be described in particular. For the video signal transmitted from the signal processing unit 416, the main arithmetic unit 222 uses the correction value set by the correction value setting unit 224 in the present embodiment, as will be described later. Perform white balance correction.

  The correction value setting unit 224 sets a correction value used for white balance correction by the main calculation unit 222 according to the type of light source.

  The correction value is set as follows, for example. First, illumination light emitted from a light source is irradiated on an achromatic color (for example, white) color reference, and the color reference achromatic color is reproduced from a color signal obtained by imaging the color reference image with the image sensor 410. The correction value is calculated. For example, when acquiring red (R), green (G), and blue (B) color signals obtained by imaging a color reference image with the image sensor 410, the ratio of the respective color signals is 1: 1: 1. A correction value (gain data value) to be corrected is set. For example, when a red color signal obtained by imaging a color reference image with the image sensor 410 is (r), a green color signal is (g), and a blue color signal is (b), the green color With the signal as a reference, the gain data value (R gain) of the red color signal can be set to (g / r), and the gain data value (B gain) of the blue color signal can be set to (g / b).

In the present embodiment, when the first light source device 3A is the reference light source and the light emitted from the lamp 308A is the reference light, there is no difference from the color signal obtained by the image sensor 410 when the reference light is irradiated with the color reference. A correction value used for white balance correction for reproducing chromatic colors is defined as a first correction value. In addition, when the second light source device 3B is another light source and the light emitted from the lamp 308B is another light, the achromatic color is obtained from the color signal obtained by the image sensor 410 when the other light is irradiated with the color reference. A correction value used for white balance correction for reproducing is defined as a second correction value.
In the present embodiment, the coefficient used for the function indicating the relationship between the first correction value and the second correction value is stored in the memory 418 in advance when the endoscope 4 is manufactured. The above function is used to calculate the second correction value from the first correction value. Further, in the present embodiment, the latest correction value used for white balance correction when the reference light is used for illumination is stored in the memory 418. When there are a plurality of light sources other than the reference light source, a coefficient used for a function indicating a relationship between the first correction value and the second correction value according to the type of the other light source is stored in the memory 418. You can let it go. For example, when there is a third light source device, a function indicating the relationship between the first correction value and the third correction value, with the correction value used for white balance correction of the third light as the third correction value. The coefficients used in the above may be stored in the memory 418.

Here, Rk (first correction value) when the reference light (for example, xenon lamp light) by the first light source device 3A is used as illumination light is Rk, and B gain (first correction value) is Bk. When other light (for example, halogen lamp light) by the second light source device 3B is used as illumination light, the R gain (second correction value) is Rh, and the B gain (second correction value) is Bh. At this time, the following functions (1) and (2) are established.
_{Rh = α r · Rk + β} r ··· (1)
_{Bh = α b · Bk + β} b ··· (2)
In this case, α _r , β _r , α _b , β _r that are the coefficients of the above function may be stored in the memory 418 in advance when the processor 2 is manufactured.

If α _r is 1, α _r may not be stored in the memory 418. In this case, β _r is the difference value of Rh and Rk. That is, the function (1) is expressed by the following formula (3).
Rh = Rk + β _r (3)
Similarly, when α _b is 1, α _b may not be stored in the memory 418. In this case, β _b is the difference value of Bh and Bk. That is, the function (2) is expressed by the following equation (4).
Bh = Bk + β _b (4)

In addition, when beta _r is 0, it is not necessary to store the beta _r in the memory 418. In this case, α _r is the ratio of Rh and Rk. That is, the function (1) is expressed by the following equation (5).
Rh = α _r · Rk (5)
Similarly, when β _b is 0, β _b may not be stored in the memory 418. In this case, α _b is the ratio of Bh and Bk. That is, the function (2) is expressed by the following equation (6).
Bh = α _b · Bk (6)

The coefficient of the function can be calculated, for example, when the endoscope system 1 is shipped as described below and stored in the memory 418.
FIG. 4 is a flowchart showing a method for calculating a coefficient and storing it in the memory 418.
First, the first light source device 3 </ b> A is connected to the processor 2 and the endoscope 4. Next, the illumination light emitted from the first light source device 3A is irradiated on the color reference, and the color reference achromatic color is reproduced from the color signal obtained by capturing the color reference image with the image sensor 410. Correction values Rk and Bk are calculated by the correction value setting unit 224 (step S1).

  Next, the second light source device 3B is connected to the processor 2 and the endoscope 4. Next, the illumination light emitted from the second light source device 3B is irradiated with the color reference, and the color reference achromatic color is reproduced from the color signal obtained by imaging the color reference image with the image sensor 410. Correction values Rh and Bh are calculated by the correction value setting unit 224 (step S2).

Next, using the correction values Rk and Bk calculated in step S1 and the correction values Rh and Bh calculated in step S2, a coefficient of a function between them is calculated (step S3). In addition, assuming that the above functions (3) and (4) are used, the difference value β _r between Rh and Rk and the difference value β _b between Bh and Bk may be calculated as coefficients. Further, assuming that the above functions (5) and (6) are used, the ratio α _r of Rh and Rk and the ratio α _b of Bh and Bk may be calculated as coefficients.
Thereafter, the calculated coefficient is recorded in the memory 418 (step S4). Thus, the process for storing the coefficients in the memory 418 is completed.

The correction value setting unit 224 uses the first correction value when the reference light from the first light source device 3 </ b> A is illumination light and the coefficient of the function stored in the memory 418 to use the second light source device. A second correction value used when other light from 3B is used as illumination light is calculated.
For example, when the reference light from the most recently used first light source device 3A is illumination light and the R gain is R1 and the B gain is B1, the light source device is changed from the first light source device 3A to the second light source device. When switching to 3B, the correction value setting unit 224 can calculate the second correction values Rh and Bh using the functions (1) and (2) as follows.
_{Rh = α r · R1 + β} r ··· (7)
_{Bh = α b · B1 + β} b ··· (8)

  When the light source device is switched from the first light source device 3 </ b> A to the second light source device 3 </ b> B, the correction value setting unit 224 uses the second correction value calculated by the correction value setting unit 224 as a white balance by the main calculation unit 222. The correction value is set as a correction value used for correction, and the main calculation unit 222 performs white balance correction by using the second correction value.

In the present embodiment, when the first light source device 3A is connected to the processor 2 and the endoscope 4, the white balance correction is calibrated once to calculate the first correction value. Even when switching from the first light source device 3A to the second light source device 3B, the newly calculated first correction value and the coefficients α _r , β _r , α _b , β _b stored in the memory 418 are used. The second correction value can be calculated using the second correction value, and the calculated second correction value can be set as a white balance correction value for other light.

Here, the first correction values (R gain and B gain) calculated by performing white balance correction calibration when the first light source device 3A is connected to the processor 2 and the endoscope 4 are R1 and B1, respectively. If R1 and B1 are stored in the memory 418, when the first light source device 3A is connected to the processor 2 and the endoscope 4, R1 and B1 are read from the memory 418 and the white balance is read. Correction can be performed.
That is, when the first connection signal is input from the system controller 202 to the video signal processing unit 220, or when the second connection signal is not input from the system controller 202 to the video signal processing unit 220, the correction value setting unit In step 224, the first correction values R1 and B1 read from the memory 418 are set as white balance correction values.

On the other hand, when the second light source device 3B is connected to the processor 2 and the endoscope 4, the second correction value calculated using the first correction values R1 and B1 and the above function is used as the other light. The white balance correction is performed using the white balance correction value.
That is, when the first connection signal is not input from the system controller 202 to the video signal processing unit 220, or when the second connection signal is input from the system controller 202 to the video signal processing unit 220, the correction value setting unit 224 reads out the first correction values R1, B1 and the coefficients α _r , β _r , α _b , β _r from the memory 418, and uses the second correction value calculated using the above function as a white balance correction for other light. This is set as the white balance correction value used for.

Next, the operation when the light source device is switched from the first light source device 3A to the second light source device 3B in the endoscope system 1 will be described.
First, the second light source device 3B is connected to the processor 2 and the endoscope 4, and operation of the operation panel 218 is set to use the second light source device 3B. Then, the system controller 202 stops outputting the first connection signal or starts outputting the second connection signal. Next, the correction value setting unit 224 reads the first correction values R1, B1 and the coefficients α _r , β _r , α _b , β _r from the memory 418, and uses the second correction value calculated using the above function. Set as white balance correction value for other light. Thereafter, the main calculation unit 222 performs white balance correction of the video signal using the set white balance correction value.

  Thus, in the endoscope system 1 of the present embodiment, even when the illumination light is switched to one having a different color temperature, the white balance correction value can be easily adjusted according to the color temperature of the illumination light after switching. And the collapse of the color balance of the observed image can be suppressed.

  In the above embodiment, the white balance correction value is set in the video signal processing unit 220 of the processor 2, but the white balance correction value may be set in the signal processing unit 416 of the endoscope 4. . In this case, by outputting the first connection signal or the second connection signal from the system controller 202 to the signal processing unit 416, the signal processing unit 416 determines either the first correction value or the second correction value as the white balance correction value. It may be determined whether to set as.

Note that it is conceivable that the color temperature of the lamp 308A or the lamp 308B changes from the factory shipment due to a change with time. In this case, it is preferable that the correction value setting unit 224 updates the coefficient recorded in the memory 418 to a newly calculated coefficient. Specifically, first, a white balance correction value of the reference light or other light after the change of the color temperature is newly calculated. Thereafter, the correction value setting unit 224 newly calculates a coefficient used for a function indicating the relationship between the white balance correction value of the reference light and the white balance correction value of the other light, and the coefficient recorded in the memory 418 is calculated. Update to the newly calculated coefficient.
As described above, even when the color temperature of the lamp 308A or the lamp 308B changes due to the change over time, the color balance of the observation image can be prevented from being lost corresponding to the change in the color temperature by updating the coefficient.

<Modification>
FIG. 5 is a block configuration diagram showing a main configuration of an endoscope system 1B according to a modification of the present embodiment. In addition, about the structure similar to the said embodiment, the same code | symbol is attached | subjected and description is omitted.

The endoscope system 1B in the present modification further includes a light source system 3C having a plurality of light sources in addition to the processor 2, the first light source device 3A, the endoscope 4, and the display 5.
The light source system 3C includes a plurality of lamps 308C and 308D, and lamp power drivers 306C and 306D that drive the plurality of condenser lenses 310C and 310D and the lamps 308C and 308D, respectively, that collect the light of the lamps 308C and 308D, respectively. Etc. The light source system 3C includes a system driver 304 that drives the lamp power drivers 306C and 306D in accordance with a signal input from the system controller 202.

The lamp 308C is lit by the power supplied from the lamp power driver 306C and emits light. Similarly, the lamp 308D is lit by the power supplied from the lamp power driver 306D and emits light. High-intensity lamps such as xenon lamps, halogen lamps, and metal halide lamps are suitable for the lamps 308C and 308D. Further, as the lamps 308C and 308D, LED (Light Emitting Diode) lamps may be used.
In this modification, the color temperatures of the light emitted from each of the lamp 308A, the lamp 308C, and the lamp 308D are different. For example, a xenon lamp can be used as the lamp 308A, a halogen lamp can be used as the lamp 308C, and a strobe lamp can be used as the lamp 308D.

  In the present modification, the light guide member 404 is connected to either the first light source device 3A or the light source system 3C. The light source system 3C selectively emits light from the lamp 308C or the lamp 308D while being connected to the light guide member 404, and the system driver 304 guides light emitted from the lamp 308C or the lamp 308D. The optical members including the condensing lenses 310C and 310D and the light guide member 404 are controlled so as to enter the member 404.

  In this modification, the system controller 202 controls the system driver 304 so that the light of the lamp 308C or the lamp 308D is incident on the light guide member 404 in the light source system 3C.

For example, when the lamp 308 </ b> C is selected on the operation panel 218, the system controller 202 outputs a third connection notification that instructs the system driver 304 to cause the light of the lamp 308 </ b> C to enter the light guide member 404. To do. At this time, the system controller 202 outputs a third connection signal for setting a white balance correction value (third correction value) corresponding to the lamp 308 </ b> C to the video signal processing unit 220.
The system controller 202 also outputs a fourth connection notification to the system driver 304 that instructs the system driver 304 to cause the light of the lamp 308D to enter the light guide member 404 when the lamp 308D is selected on the operation panel 218. To do. At this time, the system controller 202 outputs a fourth connection signal for setting a white balance correction value (fourth correction value) corresponding to the lamp 308 </ b> D to the video signal processing unit 220.
The memory 418 uses a coefficient used for a function indicating the relationship between the first correction value and the third correction value, and a function indicating a relationship between the first correction value and the fourth correction value. The coefficients to be stored are stored. The video signal processing unit 220 can calculate the third correction value or the fourth correction value in the same manner as calculating the second correction value.

FIG. 6 is a flowchart showing the operation of the endoscope system 1B when the light source is switched.
First, one of the lamps 308A, 308C, and 308D is selected on the operation panel 218 (step S11). Then, a signal corresponding to the selection on the operation panel 218 is input to the system controller 202, and the system controller 202 instructs to switch to the selected light source (step S12). When the lamp 308C is selected on the operation panel 218, the system controller 202 outputs a third connection notice to the system driver 304. When the lamp 308D is selected on the operation panel 218, the system controller 202 sends a fourth connection notice to the system. Output to the driver 304.

  Next, the system controller 202 outputs a connection signal to the video signal processing unit 220 in order to set a correction value corresponding to the selected light source (step S13). Thereafter, the video signal processing unit 220 sets a correction value according to the connection signal input from the system controller 202. When the third connection signal is input, the video signal processing unit 220 calculates a third correction value and sets it as a white balance correction value. On the other hand, when the fourth connection signal is input, the video signal processing unit 220 calculates the fourth correction value and sets it as the white balance correction value.

  Thus, even in this modification, even when switching illumination light to a plurality of light sources having different color temperatures, the white balance correction value can be easily adjusted according to the color temperature of the illumination light after switching, The collapse of the color balance of the observation image can be suppressed.

  In this modification as well, the video signal processing unit 220 of the processor 2 sets the white balance correction value, but the signal processing unit 416 of the endoscope 4 sets the white balance correction value. Also good. In this case, by outputting the first connection signal, the third connection signal, or the fourth connection signal from the system controller 202 to the signal processing unit 416, the signal processing unit 416 causes the first correction value, the third correction value, or the It may be determined which of the four correction values is set as the white balance correction value.

The endoscope system of the present embodiment has been described in detail above. However, the endoscope system of 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.
The endoscope system according to the present embodiment is preferably a respiratory endoscope system or a digestive endoscope system. Moreover, it is more preferable that the vocal cord endoscope system is effective for observation with a strobe light source.

1, 1B Endoscope system 2 Processor 3A First light source device 3B Second light source device 4 Endoscope 5 Display 200 Connector unit 201 Memory 202 System controller 218 Operation panel 220 Video signal processing unit 222 Main calculation unit 224 Correction value Setting unit 300A, 300B Connector unit 304 System driver 306A, 306B, 306C, 306D Lamp power supply driver 308A, 308B, 308C, 308D Lamp 310A, 310B, 310C, 310D Condensing lens 402 Tip portion 404 Light guide member 406 Light distribution lens 408 Objective lens 410 Image sensor 412 Amplifier 414 Connector unit 416 Signal processing unit 418 Memory (recording unit)
420 Insertion part 422 Hand operation part 424 Bending part

Claims (5)

A reference light source that emits reference light of a predetermined color temperature;
At least one other light source that emits other light having a different color temperature from the reference light source;
A light guide member that is alternatively connected to the reference light source or the other light source, and selectively irradiates the subject with the reference light or the other light;
Switching means for switching which light of the reference light source or the other light source is irradiated to the subject;
An image sensor that captures an image of the subject and generates a color signal;
A white balance correction unit for correcting white balance of the color signal;
A correction value setting unit for setting a white balance correction value used for the white balance correction;
A recording unit in which a coefficient used for a function indicating a relationship between the white balance correction value of the reference light and the white balance correction value of the other light is recorded in advance;
When the correction value setting unit sets a new white balance correction value to be used for white balance correction of the reference light source, and the switching means switches the reference light source to the other light source, the white balance The correction unit calculates a white balance correction value of the other light source using the new white balance correction value and the coefficient, and performs white balance correction of the other light source.
An endoscope system characterized by that. A first connection signal indicating that the light guide member is connected to the reference light source or a second connection signal indicating that the light guide member is connected to the other light source is output to the white balance correction unit. Connection detecting means for
The endoscope system according to claim 1, wherein the white balance correction unit calculates a white balance correction value of the other light when the second connection signal is input.   The white balance correction unit calculates a white balance correction value of the other light using a difference value between a white balance correction value of the reference light and a white balance correction value of the other light as the coefficient. The endoscope system according to 1 or 2.   The white balance correction unit calculates a white balance correction value of the other light using a ratio of a white balance correction value of the reference light and a white balance correction value of the other light as the coefficient. Or the endoscope system of 2.   When the color temperature of the reference light or the other light changes, the correction value setting unit newly calculates a white balance correction value of the reference light or other light after the change of the color temperature, and A coefficient used for a function indicating a relationship between the white balance correction value and the white balance correction value of the other light is newly calculated, and the coefficient recorded in the recording unit is updated to the newly calculated coefficient. The endoscope system according to any one of claims 1 to 4.

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