JP2002209844A - Processor for electronic endoscope - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a processor for an endoscope which is capable of photographing bright still images free of blurs with respect to photographing of an observation site. SOLUTION: This processor for the endoscope is used in an electronic scope having an illumination section and an imaging means for photographing an observation site by accumulating the charges corresponding to the optical image formed on a photodetecting surface only when the observation site is illuminated in a prescribed accumulation period. The processor has a first light emitting means for continuously emitting light, a second light emitting means for intermittently emitting the light only for a prescribed time, an optical path switching means disposed in a prescribed position where the optical paths of the light emitted from the respective light emitting means intersect with each other to guide only the light emitted from either one light emitting means to the illumination section and an optical attenuation means arranged only at least the one light emitting means to specify the luminance of the first light emitting means and the luminance of the second light emitting means to a prescribed relation.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a processor for an electronic endoscope.

[0002]

2. Description of the Related Art Generally, an electronic endoscope for observing the inside of a body includes a processor unit having a light source unit and an image processing unit;
And a scope section which is inserted into the body and illuminates the inside of the body and performs photographing at the same time. 2. Description of the Related Art In recent years, electronic endoscopes have not only observed, as a moving image, a picture taken while constantly illuminating an observation site, but also observed an image of the observation site at a desired moment on a monitor and used a film or the like. There is a demand for obtaining a still image (frozen image) to be recorded on a recording medium and used as medical treatment data.

A conventional electronic endoscope uses a processor equipped with a normal light source such as a xenon light source that can be continuously turned on. In addition, a CCD (Charge-Coupled Dev) mounted on the scope (electronic scope) of an electronic endoscope
Ice) performs photographing (imaging) by accumulating electric charges corresponding to an optical image formed on a light receiving surface by incident light.
Therefore, when a moving image is photographed using a conventional endoscope, the observation region is constantly illuminated using continuous light (hereinafter, referred to as continuous light) normally emitted from a light source. Thus, the state of the observation region that is constantly illuminated can be captured as a moving image by an imaging operation in which charge accumulation and charge readout are periodically repeated. In the case of obtaining a still image, one image corresponding to a desired moment in the images obtained by the above-described imaging operation is set as a freeze image.

However, a frozen image is an image captured under illumination of continuous light, like a moving image.
If the observed part moves during the charge accumulation period on the CD light receiving surface, a blurred still image is captured, and it is difficult to confirm a lesion or the like, which is not preferable. Image blur
This is particularly noticeable when the observation site is moving relatively fast.

[0005]

SUMMARY OF THE INVENTION Accordingly, the present invention has been made in view of the above circumstances, and relates to the photographing of a frozen image of an observation region, and an object of the present invention is to provide an endoscope processor capable of photographing a clear still image without blurring. Aim.

[0006]

For this reason, an electronic endoscope processor according to claim 1 is formed on the light receiving surface only when the diseased part is illuminated during the predetermined storage period. The present invention is used for an electronic scope having an imaging unit for photographing the affected part by accumulating electric charges corresponding to an optical image. The processor intersects a first light emitting means for continuously emitting light, a second light emitting means for intermittently emitting light for a first predetermined time, and an optical path of light emitted from each light emitting means. At a predetermined position, only the irradiation light from the second light emitting unit is guided to the illumination unit only during a second predetermined period, and the irradiation from the first light emitting unit is performed during a period other than the second predetermined period. An optical path switching unit that guides only light to the illumination unit, and at least one of the light emitting units, and a predetermined relationship between the illuminance of the irradiation light by the first light emitting unit and the illuminance of the irradiation light by the second light emitting unit. Optical attenuating means.

[0007] According to the above configuration, a single processor can capture an image with light emitting means suitable for a moving image and a still image. In addition, by adjusting the illuminance of each light emitting unit, it is possible to always capture a moving image and a still image with desired brightness.

[0008] The predetermined relationship can be set so that images captured by light emitted from either light emitting means have the same brightness (claim 2). Thereby, the brightness of the image observed on the monitor does not vary between the moving image and the still image.

According to a third aspect of the present invention, a processor for an electronic endoscope accumulates a charge corresponding to an optical image formed on a light receiving surface only when an observation portion is illuminated during a predetermined accumulation period. This is used for an electronic scope having an imaging means for taking an image of an observation site. The processor intersects a first light emitting means for continuously emitting light, a second light emitting means for intermittently emitting light for a first predetermined time, and an optical path of light emitted from each light emitting means. At a predetermined position, only the irradiation light from the second light emitting unit is guided to the illumination unit only during a second predetermined period, and the irradiation from the first light emitting unit is performed during a period other than the second predetermined period. An optical path switching unit that guides only light to the illumination unit; and a signal amplifying unit that amplifies a video signal transmitted from the imaging unit to a predetermined level after accumulating charge by irradiation light from each light emitting unit guided by the optical path switching unit. It is characterized by having.

According to the present invention, the same effect as that of the first aspect can be obtained.

According to the processor for an electronic endoscope of the present invention, the signal amplifying means amplifies the video signal to a predetermined level based on the gain data generated based on the luminance of each light emitting means. It is desirable.

According to the processor for an electronic endoscope according to the present invention, it is desirable that the brightness is set so as to be optimal when observing the photographed image.

[0013] According to the electronic endoscope processor of the present invention, the continuous light emitted from the first light emitting means is further arranged on the optical path of the light guided to the illumination unit by the optical path switching means. When the light is emitted, the continuous light is adjusted so as to have a predetermined light amount, and when the intermittent light emitted from the second light emitting means is incident, the light adjusting means is fixed in the immediately preceding light adjusting state. be able to.

According to the electronic endoscope processor of the present invention, there is provided a light emitting instruction means for instructing irradiation from the second light emitting means, and the optical path switching means corresponds to the instruction of the light emitting instruction means. It is preferable that the light emitted from the second light emitting means is guided to the lighting section only when the second light emitting means emits light. As a result, observation with normal light is normally continued, and a still image can be taken at an arbitrary timing.

[0015]

FIG. 1 is a schematic diagram of an endoscope 100α according to a first embodiment of the present invention. The endoscope 100α is
It comprises a processor 100a and a scope unit 100b. The processor 100a includes a xenon light source 1, a strobe light source 2, a mirror 3, a mirror drive unit 4, an aperture 5, an aperture drive unit 5a, a condenser lens 6, a main control unit 7, an operation panel 8, an optical filter 9, an image processing circuit. 20 and a light guide 30. The scope unit 100b includes the CCD 1
0, having a light guide tip 30a.

The xenon light source 1 is a light source that can emit continuous light, and the strobe light source 2 is a high-luminance light source that can emit flash light for a predetermined time. The endoscope 100α uses the xenon light source 1 when photographing the observation region as a moving image, and uses the strobe light source 2 when photographing and recording the observation region as a still image. In this specification, photographing an observation region as a moving image is referred to as normal imaging, and photographing a desired moment of the observation region as a still image (freeze image) is referred to as flash photography.

Here, the CCD 10 provided in the scope section 100b takes a time from one charge read pulse to the reception of the next charge read pulse, in other words, a time between one transfer period and the next transfer period. Photographing is performed by accumulating charges corresponding to the optical image formed on the light receiving surface by light incident during the charge accumulation time (hereinafter referred to as charge accumulation time). That is, the brightness of the captured image is
And the time when the CCD 10 actually accumulates electric charges.

At the time of normal photographing, continuous light always enters the CCD 10, so that the time for which the CCD 10 actually accumulates charges is equal to the charge accumulable time. Also, when shooting with flash,
Since the CCD 10 accumulates electric charges only when a flash is incident, the time for which the CCD 10 actually accumulates electric charges is equal to the flash emission time of the strobe light source 2 during the electric charge accumulable time. It is assumed that one flash light emission time of the strobe light source 2 is relatively short with respect to a charge accumulable time of the CCD. Since the endoscope 100 is configured to always apply the charge readout pulse to the CCD 10 at a predetermined interval, the charge accumulable time is always constant. Since the flash emission time is determined by the emission specification of the strobe light source 2 to be used,
After all it is constant.

Therefore, if the brightness of the light sources 1 and 2 is adjusted,
It is possible to shoot an image with optimal brightness both in normal shooting and in flash shooting. Specifically, at the time of initial setting at the time of product shipment and light source replacement, light is actually emitted from each of the light sources 1 and 2, and the brightness of a captured image is measured. As described above, the charge accumulation time of the CCD 10 at each shooting is known in advance. Therefore, it is possible to calculate the illuminance of each of the light sources 1 and 2 necessary for making the brightness of the image obtained at each photographing optimum for observation based on the measurement result. After that, based on the calculation result, the irradiation light from each of the light sources 1 and 2 may be adjusted to have a predetermined illuminance.

In the endoscope 100α of this embodiment, by providing the xenon light source 1 and the strobe light source 2 with the optical attenuation filter 9, each of the light sources 1 and 2 is required to obtain an image of optimal brightness. It is adjusted to have brightness.
In FIG. 1, for convenience, it is assumed that the brightness of an image during normal shooting is the optimum brightness. Therefore, since there is no need to adjust the illuminance, the xenon light source 1 is not provided with the filter 9, but the strobe light source 2 is provided with the filter 9 that attenuates a still image by a predetermined amount in order to optimize the brightness. The illuminance is adjusted.

The mirror 3 is provided to guide only one of the lights from the light sources 1 and 2 to the scope section 100b via the light guide 30. Mirror 3
Is connected to the mirror driving unit 4 and is in a drivable state. The mirror driving unit 4 drives the mirror 3 under the control of the main control unit 7. Specifically, during normal photographing, the mirror 3 is retracted outside the optical path of the continuous light, and the continuous light from the xenon light source 1 is guided to the diaphragm 5. Then, at the time of flash photography, the mirror 3 is arranged at a predetermined position such that the flash light emitted from the flash light source 2 is reflected and guided to the diaphragm 5. FIG.
Indicates the arrangement at the time of flash photography, that is, the mirror 3 at a predetermined position. The mirror 3 is large enough to completely block light from the xenon light source 1 when it is at a predetermined position during flash photography.

The stop 5 is provided to reduce the light emitted from each of the light sources 1 and 2 to a predetermined light beam width. Aperture 5
Is controlled by the main control unit 7 according to the shooting state, as will be described later. The condenser lens 6 converges the incident light and guides it to the light guide 30. The light that has passed through the light guide 30 is emitted from the light guide tip 30a and illuminates the affected part.

The CCD 10 transmits the photographed content to the image processing circuit 20 as a video signal. Image processing circuit 20
Performs predetermined processing on the video signal from the CCD 10 and outputs the video signal to a monitor (not shown). The monitor displays an image corresponding to the video signal.

The operation of the endoscope 100α during each photographing will be described below. The endoscope 100α is configured to perform once strobe photographing of a still image of the affected part only when a strobe photographing instruction is given from the operation panel 8, and to perform normal photographing in other cases.

At the time of normal photographing, the main control section 7 irradiates light from the xenon light source 1. At this time, the main control unit 7
Retracts the mirror 3 from the optical path of the continuous light from the xenon light source 1 via the drive unit 4. Note that the strobe light source 2 does not need to emit light during normal photographing, and is therefore turned off to save power.

The main control section 7 appropriately sends a drive signal to the drive section 5a based on the signal relating to the brightness of the image transmitted from the image processing circuit 20. Thus, the drive of the diaphragm 5 is controlled so that the light beam width of the continuous light becomes a predetermined width.

The continuous light emitted from the stop 5 passes through the condenser lens 6 and the light guide 30 to the light guide tip 30.
a illuminates the observation site. Since the photographing by the CCD 10 and the operation of the image processing circuit 20 have been described above,
The description here is omitted. During normal shooting, the CCD 10
Is constantly taking a picture and transmitting a video signal to the image processing circuit 20. Therefore, the image on the monitor is also sequentially updated with the captured image (still image) that changes every moment, and the moving image can be observed. Since the signal regarding the brightness of the image transmitted from the image processing circuit 20 is always transmitted, the main control unit 7 always controls the drive of the aperture 5. The above is the operation of the endoscope 100α during normal imaging.

Next, the operation of the endoscope 100α when the photographer operates the operation panel 8 to instruct flash photography will be described. When flash photography is instructed, the main control unit 7
The mirror 3 is disposed at a predetermined position via the drive unit 4 as shown in FIG. Further, the main control unit 7 fixes the aperture 5 at the same time as switching from the normal shooting to the flash shooting. As described above, since the illuminance of the irradiation light from each of the light sources 1 and 2 is adjusted in advance by the filter 9 in accordance with the brightness of the image, the limitation of the light amount by the aperture is maintained the same even when the imaging method is switched. That is because it is good. That is, flash photography is performed in the same state as the aperture immediately before switching from normal photography to flash photography.

When the driving of the mirror 3 and the fixing of the diaphragm 5 are completed, the main control section 7 causes the strobe light source 2 to emit a flash once. The flash light from the strobe light source 2 is
After being reflected by the light guide tip 3 through the condenser lens 6 and the light guide 30 in the same manner as the continuous light at the time of normal shooting
The body is illuminated from 0a.

In the photographing of the CCD 10 by flash light, it is possible to obtain a still image having a high luminance and a short light emission time, and a clear image without blurring, yet having the optimal brightness for observation. The image processing of the image processing circuit 20 is as follows.
Since the operation is the same as that in the normal photographing described above, the description is omitted here. Note that a still image (frozen image) obtained instead of displaying a moving image by normal shooting is always displayed on the monitor. In this way, the photographer can observe the still image on the monitor, print the image with a video printer, or record the image on a recording medium such as a film.

When the flash photography ends (that is, the flash emission ends), the endoscope 100α performs an operation of automatically returning to the illumination state of the normal photography. That is, the mirror 3 is retracted outside the optical path of the continuous light. Next, when the photographer operates the operation panel 8 to instruct the normal shooting, the fixing of the aperture 5 is released, and the moving image can be observed by the normal shooting again. In this embodiment, the darkening time on the monitor is shortened as much as possible, so that switching between normal shooting and flash shooting can be performed without discomfort of the photographer, even during flash shooting.
The xenon light source 1 is controlled to emit continuous light. Even if continuous light is emitted from the xenon light source 1 during flash photography, the continuous light is completely shielded by the mirror 3, so there is no particular problem. The above is the first embodiment.

FIG. 2 shows an endoscope 1 according to a second embodiment of the present invention.
00β. 2, the same components as those shown in FIG. 1 are denoted by the same reference numerals, and description thereof will be omitted.
In the endoscope 100β, the light sources 1 and 2 are not provided with a filter. The endoscope 100β includes a signal amplification circuit 20a in the image processing circuit 20.

In the case of the second embodiment, light is actually emitted from each of the light sources 1 and 2 at the time of initial setting at the time of product shipment of the endoscope 100β and at the time of light source replacement. Next, the video signal level transmitted from the CCD 10 at the time of normal photographing and strobe photographing is compared with the signal level (reference level) of an image having the optimum brightness required for observation. Then, a gain required to make the signal level of the video signal at each shooting equal to the reference level is calculated, and the gain is stored in a memory (not shown) in the main control unit 7 as data corresponding to each shooting. Keep it.

When photographing is actually performed, the main control section 7 reads out gain data corresponding to normal photographing or strobe photographing and transmits it to the amplifier circuit 20a. The amplifying circuit 20a appropriately adjusts C to correspond to the transmitted gain data.
The signal level of the video signal transmitted from the CD 10 is amplified. Thereby, the signal level of the video signal output to the monitor is always the same, and a moving image and a still image having optimal brightness for observation can be obtained. Further, since the other mechanisms are the same as those of the first embodiment, the still image is naturally a clear image without blurring.

In the second embodiment, it is not necessary to provide optical attenuating means for each of the light sources 1 and 2, so that the processor 100a can be made compact. In addition, the second embodiment amplifies the signal level so that an image with the optimal brightness can be observed, so that the expensive high-brightness strobe light source 2 does not need to be used. The above is the description of the endoscope 100β of the second embodiment.

The above is the embodiment of the present invention. The present invention is not limited to these embodiments, and various modifications can be made without departing from the gist.

In the first embodiment, the brightness of the light sources 1 and 2 is adjusted using the filter 9. However, it is possible to use an optical attenuating means other than the filter.

In each of the above embodiments, the optimum brightness for observation of both moving images and still images has been described as being constant, but the present invention is not limited to this. By changing the data relating to the attenuation factor and gain of the optical attenuation filter 9, it is possible to arbitrarily brighten (or darken) a still image by a certain amount than a moving image.

In each of the above embodiments, the xenon light source 1 is always turned on so as to emit light during flash photography. However, if the xenon light source 1 is turned off during flash photography, power saving can be achieved.

In each of the above embodiments, the mirror 3 is arranged at a predetermined position in the optical path so as to guide the light of the strobe light source 2 to the light guide 30 at the time of flash photography. However, the arrangement may be such that the xenon light source 1 and the strobe light source 2 are interchanged, the mirror 3 is arranged at a predetermined position in the optical path during normal photographing, and the mirror 3 is retracted from the optical path during strobe photographing. Switching between normal shooting and flash shooting may be performed not only by the operation panel but also by a button provided on the operation unit of the scope unit.

[0041]

As described above, the endoscope of the present invention is provided with two light sources having different light emission specifications for normal photographing and strobe photographing, and adjusts the brightness of each light source and amplifies the signal level of a video signal. By doing so, a moving image or a clear still image without blur can be photographed and observed with appropriate brightness.

[Brief description of the drawings]

FIG. 1 is a schematic configuration diagram of an endoscope according to a first embodiment of the present invention.

FIG. 2 is a schematic configuration diagram of an endoscope according to a second embodiment of the present invention.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Xenon light source 2 Strobe light source 3 Mirror 5 Aperture 7 Main control unit 9 Optical attenuation filter 10 CCD 100α, 100β Endoscope

 ──────────────────────────────────────────────────続 き Continuing on the front page (72) Inventor Hiroyuki Kobayashi 2-36-9 Maenocho, Itabashi-ku, Tokyo Asahi Gaku Kogyo Co., Ltd. (72) Inventor Ryo Koike 2-36-9 Maenocho, Itabashi-ku, Tokyo No. Asahi Gaku Kogyo Co., Ltd. F-term (reference) 2H040 BA09 CA10 GA02 GA10 GA12 4C061 CC06 GG01 RR02 RR14 5C054 CA04 CB03 CC07 CH07 ED03 FA00 FF02 HA12

Claims (9)

[Claims] 1. An illuminating unit and an imaging unit for capturing an image of an observation region by accumulating charges corresponding to an optical image formed on a light receiving surface only when the observation region is illuminated during a predetermined accumulation period. A first light-emitting means for continuously irradiating light; a second light-emitting means for intermittently irradiating light for a first predetermined time; and The light emitting unit is disposed at a predetermined position where an optical path of light to be irradiated intersects, and guides only the irradiation light from the second light emitting unit to the illumination unit for a second predetermined period, and
A light path switching unit that guides only the irradiation light from the first light emitting unit to the lighting unit during a period other than the predetermined period, and an illuminance of the irradiation light by the first light emitting unit, which is disposed in at least one of the light emitting units. An optical attenuating means for setting the illuminance of irradiation light from the second light emitting means in a predetermined relationship. 2. The processor for an electronic endoscope according to claim 1, wherein the predetermined relationship is such that images captured by light emitted from either one of the light emitting units have the same brightness. An electronic endoscope processor. 3. An illuminating unit and an imaging unit for capturing an image of the observation region by accumulating charges corresponding to an optical image formed on the light receiving surface only when the observation region is illuminated during a predetermined accumulation period. A first light emitting means for continuously emitting light, and a second light emitting means for intermittently emitting light for a first predetermined time. A light source for irradiating the light emitted from each light emitting means at a predetermined position where the light path intersects the light path, and guiding only the light emitted from the second light emitting means to the lighting unit for a second predetermined period;
During a period other than the predetermined period of time, an optical path switching unit that guides only the irradiation light from the first light emitting unit to the illumination unit, and after accumulating charge by the irradiation light from each of the light emitting units guided by the light path switching unit, A signal amplifying means for amplifying the video signals transmitted from the imaging means to respective predetermined levels, the processor for an electronic endoscope. 4. The electronic endoscope processor according to claim 3, wherein the signal amplifying unit converts the video signal to a predetermined level based on data relating to a gain generated based on luminance of each light emitting unit. Amplifying, a processor for an electronic endoscope. 5. The processor for an electronic endoscope according to claim 3, wherein the predetermined level is a level at which images captured by light emitted from either one of the light emitting units have the same brightness. A processor for an electronic endoscope, wherein: 6. The electronic endoscope processor according to claim 2, wherein the brightness is an optimal brightness when observing the photographed image. Endoscope processor. 7. The electronic endoscope processor according to claim 1, further comprising an optical path switching unit disposed on an optical path of light guided to the illumination unit by the optical path switching unit. When the continuous light emitted from the light emitting means enters, the light is adjusted so that the continuous light has a predetermined light amount, and when the intermittent light emitted from the second light emitting means enters, An electronic endoscope processor, comprising: a dimming unit fixed in a dimming state. 8. The electronic endoscope processor according to claim 1, further comprising: a light emission instructing unit for instructing irradiation from the second light emitting unit, wherein the light path switching is performed. Means for guiding the light emitted from the second light emitting means to the lighting unit only when the second light emitting means emits light in response to the instruction of the light emitting instruction means. Mirror processor. 9. The electronic endoscope processor according to claim 1, wherein the optical path switching member is provided from one of the first light emitting unit and the second light emitting unit. When the light to be irradiated is guided to the lighting unit, the light is retracted from a predetermined position, and is predetermined only when the light to be irradiated from the other of the first light emitting unit and the second light emitting unit is guided to the lighting unit. A processor for an electronic endoscope, wherein the processor is inserted into a position.