JPH0416170B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention provides an endoscope device that selectively uses a strobe light source and a collimation light source to observe and photograph the inside of a body cavity. The present invention relates to a photographing device for an endoscope device that prevents the occurrence of a no-image state during observation on a monitor.

In general, in the camera of an endoscope device that has a built-in solid-state image sensor such as a CCD or BBD, as a unique characteristic of this solid-state image sensor, at least one
If the solid-state imaging device is not kept in a dark state for a period longer than a field or one frame scanning period, the light from both light sources will be mixed, resulting in a so-called fogging phenomenon. This is due to the difference in emission spectra between a collimation light source, usually a halogen lamp, and a strobe light source, usually a xenon lamp. Further, during this period of darkness, there is no image on the monitor screen, which causes anxiety to the viewer.

An object of the present invention is to provide an endoscope apparatus that selectively uses two or more types of light sources, which avoids fogging caused by different types of light sources and also avoids anxiety on the part of the observer. There is a particular thing.

The photographing device for an endoscope apparatus of the present invention includes a camera control means for extracting an image signal and a synchronization signal generated every one field or one frame scanning period from a camera incorporating a solid-state image sensor, and an image capturing device from the camera control means. main memory means for sequentially storing signals; release detection means for detecting the operation of a shutter release button for flash photography and generating a release detection signal; and reception of the synchronization signal that arrives only after the release detection signal is detected. light source sequence means for generating a timing signal for starting post-stroboscopic photography; sub-memory means for temporarily storing the image signal by receiving the timing signal; and sub-memory means for temporarily storing the image signal by receiving the timing signal. , switching means for switching from the main memory means to the sub memory means.

The present invention will be described in detail below with reference to the drawings.

Since the configuration of the endoscope apparatus is known, it will be briefly explained with reference to FIG. This endoscope device 10
includes an image guide section 12, an operation section 14 consisting of a shutter/release button, etc., a light guide section 16, a light source device 18, and a camera section 20.
It is composed of. First, the mirror 22 inside the light source device 18 is tilted toward the collation lamp 24,
For example, the light guide section 16 made of glass fiber
A collation light is emitted from the distal end portion 17 through a light guide optical path provided inside the operating portion 14 and the image guide portion 12 from one end portion of the image guide portion 12 . on the other hand,
When the image guide section 12 is inserted into the body cavity from its distal end 17, the light guide section 16
An image guide section 12 made of glass fiber, for example, forming an optical path separate from the fiber optical path of
Through the optical path, the observation image of the body cavity irradiated with the collation light is introduced from the distal end 17 to the camera section 20, where it is converted into an electrical signal by a solid-state image sensor.
In order to superimpose a synchronization signal or the like on this signal and extract it as a TV signal, this converted electrical signal is processed by a processing circuit 26, which will be described later, and then observed on a monitor 28.

In addition, in the case of photographing with a strobe, the mirror 22 is excluded from the optical path of the strobe lamp 30, and the shutter release button 32 is
is pressed to cause the strobe lamp 30 to emit light at a desired instant. A control circuit 34 is provided in the light source device 18 for determining the start instant and end instant of the light emission duration of this strobe light emission.

FIG. 2 shows an electronic circuit of an embodiment of the photographing apparatus of the present invention. The portion surrounded by the broken line in the figure corresponds to the processing circuit 26 in FIG. The output terminal of the camera unit 20 containing a solid-state image sensor is connected to the camera control circuit 50, one of the output terminals is connected to a main memory device 52 consisting of a desk memory or a tape memory device, and the other is connected to an image signal. is connected to a sub-memory device 54 that temporarily stores the information. As this sub-memory device 54, for example, a CCD memory, CTD memory, IC memory, etc. can be used. However, since the signal from the solid-state image sensor is an analog signal, it is necessary to convert this analog signal into a predetermined digital signal when using a digital memory such as an IC memory.
Also, the TV image signal from the camera control circuit 50 is sent to the monitor 2 via the normally closed contact NC of the display switching circuit 56.
8.

On the other hand, the release button 32 is connected to a release detection circuit 58 that detects the pressing operation of the shutter release button 32 and generates a release signal. The output terminal of this detection circuit 58 is connected to the light source sequence circuit 6.
Connect to 0. A sequence control signal from this sequence circuit 60 is supplied to the sub-memory device 54 and the display switching circuit 56. Further, the image output signal from the sub-memory device 54 is selectively supplied to the monitor 28 via the normally open contact NO of the display switching circuit 56.

Next, the operation of this circuit will be explained with reference to the waveform diagram of FIG.

First, in the endoscope device 10, since the collation lamp 24 is always lit, the camera section 2
From 0, for example, an observed image inside the body cavity is outputted as an electrical signal in a serial signal relationship for each frame scan. A camera control circuit 50 that superimposes a synchronization signal on this output signal and applies a drive voltage to the built-in solid-state image sensor is connected to the camera section 20, so the output signal from this circuit 50 is displayed on the TV monitor 28. It is a TV signal that can be displayed directly. This TV signal is supplied to the main memory device 52 and is constantly stored therein. At the same time, the display switching circuit 56
The observed image is constantly displayed on the monitor 28 via the normally closed contact NC.

Next, when the desired observation image is recognized on the monitor 28 and the shutter release button 32 is pressed at time t ₁ , a release detection signal is generated from the release detection circuit 58 and supplied to the light source sequence circuit 60 . On the other hand, this sequence circuit 60 is supplied with a TV signal from the camera control circuit 50, and extracts a transfer gate signal (used as a synchronization signal in this example) from this signal to control the strobe as described later. The light emission start timing is formed and sent to the output terminal 62. Further, in response to the release detection signal, a control signal from the output terminal 64 of this sequence circuit 60 turns off the collation lamp 24 or turns off the mirror 22 to the strobe lamp 3.
Exclude from the optical path of 0. As mentioned above, time t ₁
Even if the release button _is operated in
The illumination light is irradiated for ~ _t4 . That is, the irradiation is performed over the next field period. Therefore, the image information during the field period to which _t1 belongs is supplied from the sequence circuit 60 to the sub-memory device 54 and stored therein, and the display switching circuit 56 is connected to the contact NO.
The image is displayed on the monitor 28. To further explain this, by time t ₄ , during the transfer period t ₂ to _{t 3} by the transfer gate signal, the image signal during the field scanning period to which time t ₁ when the shutter release button 32 was operated is read out from the image sensor. be done. This image signal is displayed on the monitor 28 during the field scanning period to which time _t4 belongs, that is, the next field scanning period. During this period, the image sensor is partially irradiated with illumination light, so photography with a strobe cannot be performed during this field period (to prevent fogging). Therefore, for safety reasons, it is necessary to maintain the image pickup device in a dark state for one or more field periods following the field period to which the shutter release instant belongs. This prevents fogging caused by the illumination light. During this period of darkness, there is no image on the monitor 28 because no image information is extracted. According to the present invention, in order to avoid this situation, the image information stored in the sub-memory device 54 at time _t1 is read out and displayed on the monitor 28 until the flash photography is completed.

A sequence circuit 60 detects a transfer gate signal (transfer period) after pressing the release button 32, supplies a switching signal to the display switching circuit 56, and also supplies a control signal to the sub-memory device 54 to control the camera. It temporarily stores the TV signal from circuit 50 and continues to supply this stored information to monitor 28 for a predetermined period of time.

On the other hand, the sequence circuit 60 outputs a timing signal for strobe light emission to the strobe control circuit 34 in the light source device 18 via the output terminal 64 after one field period or more has elapsed since the above-mentioned control signal was supplied. supply After shooting with flash,
Transfer is performed from time _t5 to time _t6 , and this strobe photographed image is displayed on the monitor ₂₈ after time t6.

What should be noted here is that although an image is always displayed on the monitor 28, if this displayed image is not an image that is actually photographed by the camera section 20 at the time it is being displayed. (Of course, in this case, one field period or one field period specific to the image sensor
Display delays in frame periods shall be ignored).
That is, while the image sensor is in a dark state, previously captured images temporarily stored in the sub-memory device 54 are displayed.

Note that since the duration of the transfer gate signal is extremely short compared to the scanning period (approximately 3.35 μsec vs. approximately 16.7 msec), it is assumed that the release button is not operated during this period. but,
When the release button is operated, a delay circuit or the like may be used to delay this release signal so that it becomes equivalent to what occurs in the next field or frame.

As described in detail above, according to the present invention, it is possible to prevent the fogging phenomenon caused by the mixture of the collimation light and the strobe light, and also to prevent the viewer from feeling anxious because the image is always displayed on the monitor. There are advantages like no other.

The present invention is not limited to the embodiments described above, but can be modified in various ways.

For example, in the present application, it is possible to implement a method in which two fields are used for one frame scanning period, or a method in which one field is equal to one frame scanning period.

Furthermore, the strobe light image can be projected over several field periods, and in this case, the strobe light image can be sufficiently observed. Of course,
This strobe light image does not have to be displayed on a monitor.

Furthermore, when displaying an image on a monitor, it is also possible to display whether the image information is an image of the subject actually being observed or an image stored in the sub-memory device.

In the embodiment, the CCD transfer gate signal is used as the synchronization signal, but the present invention is not limited to this. It is also possible to generate a synchronization signal separately and use it, or to use the CCD reset signal. can.

Further, as shown in FIG. 1, the shutter release button 32 is attached to the operation section 14 of the endoscope device, but the shutter release button 32 is not limited to this, and the shutter release button 32 is attached to the camera section 2.
0 or the processing circuit 26.

Further, the operating section 14 can be detachably attached to the camera section 20.

It is clear that the present invention can also be implemented in an endoscope device with a built-in solid-state image sensor in which the camera section 20 is incorporated in the distal end section 17.

[Brief explanation of drawings]

FIG. 1 is a diagram showing the entire system in which the imaging position of the present invention is incorporated into an endoscope device, FIG. 2 is a circuit diagram of an embodiment of the imaging device of the invention, and FIG.
FIG. 3 is an operation diagram for explaining the operation of FIG. 2; 10...Endoscope device, 18...Light source device, 20
... Camera section, 26 ... Processing circuit, 32 ... Shutter release button, 50 ... Camera control circuit,
52...Main memory device, 54...Sub memory device, 56...Display switching circuit, 58...Release detection circuit, 60...Light source sequence circuit.

Claims (1)

[Claims] 1 an image guide means inserted into a body cavity;
a collimation light source that emits illumination light to illuminate the inside of the body cavity via the image guide means; a strobe light source that emits strobe light to photograph the inside of the body cavity through the image guide means; A solid-state image sensor that captures images and converts them into electrical signals;
a camera control means for taking out an image signal output by the solid-state image sensor and a synchronization signal generated every one field or one frame scanning period; an observation monitor for displaying the image signal output from the camera control means; a memory means for storing the image signal; a release means for specifying the start of photography using the strobe light; a release detection means for detecting the operation of the release means and generating a release detection signal; means for stopping irradiation of the illumination light when the release detection signal is detected; switching means for displaying the image signal stored in the memory means on the monitor in response to the release detection signal; An endoscope comprising a light source sequence means for generating a timing signal for starting strobe photography after a predetermined field or a predetermined frame scanning period by receiving the synchronization signal, and a means for causing the strobe light source to emit light in response to the timing signal. Photography device for mirror device.