JPH0228967B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a tip camera type endoscope equipped with an image sensor.

As a conventional advanced camera type endoscope, for example,
The one shown in the figure is known. In Fig. 1, 1 is a camera at the end of the endoscope, 2 is an image guide, 3 is an eyepiece, 4 is an observation lens, 5 is an imaging lens, 6 is a cassette film, 7 is a light guide, and 8 is a light source device. be. The endoscope with such a configuration has a cassette film 6 inside the distal camera section 1.
The front end camera section 1 is relatively large because it accommodates the camera, which poses a problem in terms of operability. Therefore, as shown in FIG. 2, the imaging position of the photographing lens 5 is
A solid-state image sensor 10 such as a CCD is installed, and a camera control unit 11 converts the signal from the solid-state image sensor 10 into a video signal and outputs it to a display device 12 for immediate recording, playback, and transmission of observed images, and for multiple users. However, the cable connecting the solid-state image sensor 10 and the camera control unit 11 is highly susceptible to breakage at the curved and flexible parts (not shown) of the endoscope, so it is not reliable. There is a problem with sexuality.

In view of the above points, it is an object of the present invention to provide an endoscope having the configuration shown in FIG. 2, which is capable of detecting disconnection of each wiring in the cable from the solid-state image sensor. This will be explained below with reference to the embodiment shown in the drawings. In Fig. 3, 1
3 is a cable that connects the solid-state image sensor 10 and the camera control unit 11, and is actually a cable in which multiple lines such as power supply, ground, vertical synchronization signal, horizontal synchronization signal, video signal, etc. are combined into a set;
16 is a control device that is activated when the power switch 15 of the endoscope is turned on, and 16 is a state in which the cable 13 is connected to the camera control unit 11 by the control device 14 (A), and a state in which the cable 13 is connected to a disconnection detection device 17 (described later). When the power switch is turned on, the switching device switches between state (B) and state (B) for a predetermined period of time necessary for wire breakage detection, and thereafter switches to state (A). 18 is an amplifier that amplifies the signal from the disconnection detection device 17; 19 is an alarm device that issues an alarm when a disconnection is detected based on the amplified signal from the amplifier 18.

Since the embodiment of the present invention is configured as described above, when the power switch 15 of the endoscope is turned on, the switching device 16 is first switched to the state (B) by the control device 14, and the cable 13 is switched to the state (B). is connected to a wire breakage detection device 17, a wire breakage is detected, and when a wire breakage is detected, an alarm is issued from an alarm device 19. After that, when a predetermined period of time has elapsed, the control device 14
As a result, the switching device 16 is switched to the state (A), and the cable 13 is connected to the camera control unit 11, allowing normal use.

Fig. 4 shows an example of the configuration of a disconnection detection device, where 20 is a current detection coil through which all the wires of the cable 13 pass, and 21 is a selection switch provided for all wires except the ground wire. They are turned on one by one in sequence. Further, the other end of the cable 13 is connected to the camera control unit 11. Therefore, the power switch 15
When turned on, the switching device 16 is switched to (B), and each line of the cable 13 is connected to the camera control unit via the selection switch 21, and the selection switch 21 is turned on one by one.
Therefore, if there is no disconnection at this time, a current flows through each wire, and the current detection coil 20 detects this current and outputs a signal to the alarm device 19 via the amplifier 18. If there is a disconnection, no current will flow through that line and no signal will be input to the alarm device 19 at this time, so the alarm device 19 will issue an alarm.
In this case, there is no particular detection of breakage of the ground wire, but there is no problem because when the ground wire is broken, a warning is issued for all other wires. Regarding the video signal line, an optical fiber with one end disposed near the solid-state image sensor 10 is used, since a false alarm may be issued if there is little light incident on the solid-state image sensor 10. By detecting the amount of light in the vicinity of the solid-state image sensor 10 using a light-receiving element disposed opposite to the other end surface of the lever, and comparing it with the video signal from the solid-state image sensor 10, it is possible to determine whether or not there is a disconnection. Another advantage is that the output of the light receiving element can be used for automatic dimming of the light source. Since this optical fiber does not require precision, plastic fiber can also be used.

FIG. 5 shows a second configuration example of the disconnection detection device, in which reference numeral 22 indicates a current detection coil disposed on each line of the cable 13, and 23 indicates an amplifier that selectively sequentially outputs the output of each current detection coil 22. This is a selection switch that allows input to 18. Therefore, when the power switch 15 is turned on, the switching device 16 is switched to (B), and each wire of the cable 13 is connected to the current detection coil 2.
2 and is connected to the camera control unit 11, and the selection switch 23 is sequentially pressed.
By being turned on, each current detection coil 22 detects a current and outputs a signal to the alarm device 19 via the amplifier 18 if there is no disconnection. The alarm device 19 thus operates in the same manner as described in connection with FIG. In this case as well, the ground line and video signal line are the same as those described in FIG. 4.

In both of the configurations shown in FIGS. 4 and 5, two wires are arranged in parallel, and one set is equipped with the above-mentioned disconnection detection device, and the other set is provided as a backup as shown by the chain line 13' in FIG. 3. If it is connected to the camera control unit 11 in a straight line, if a disconnection is detected, it can be switched to a spare set and repaired after use, so if the endoscope is not used in an emergency. This is particularly effective when the

Furthermore, when using a cable with a spare wire 13', a voltage is applied between a pair of wires 13a and 13a' connected in parallel for the same purpose as shown in FIG. It is also possible to sequentially detect the disconnection of each pair of wires, in which case the disconnection detection device shown in FIG. 4 can be implemented by also providing a switch 21 for the ground wire, or the configuration shown in FIG. 5 can be used as is. obtain.

As described above, according to the present invention, disconnection of each line in the cable connecting the solid-state imaging device and the camera control unit of an advanced camera type endoscope equipped with a solid-state imaging device is automatically detected before use. This is very preferable from the point of view of safety, since there is no possibility of accidentally using a broken endoscope. Furthermore, if a spare line is provided, the endoscope can be used normally by switching to the spare line when a disconnection is detected, which is particularly effective in an emergency.

[Brief explanation of drawings]

FIG. 1 is a configuration diagram showing an example of a conventional advanced camera type endoscope, FIG. 2 is a configuration diagram showing an example of an advanced camera type endoscope equipped with a solid-state image sensor, and FIG. 3 is a disconnection diagram according to the present invention. A block diagram of one embodiment of a tip camera type endoscope having a detection device, FIGS. 4 and 5 are diagrams showing an example of the configuration of a disconnection detection device, and FIG. 6 is a block diagram showing another embodiment according to the present invention. It is a diagram. 10... Solid-state image sensor, 11... Camera control unit, 12... Display device, 1
3... Cable, 14... Control device, 15... Power switch, 16... Switching device, 17... Disconnection detection device, 18... Amplifier, 19... Alarm device, 2
0, 22... Current detection coil, 21, 23... Selection switch.

Claims (1)

[Claims] 1. A display device or a recording device that is equipped with a solid-state imaging device such as a CCD disposed at the imaging position of a photographic lens, and that converts a signal from the solid-state imaging device into a video signal by a camera control unit. In the advanced camera type endoscope that outputs
A disconnection detection device that energizes each wire of a cable connecting the solid-state image sensor and the camera control unit and detects this using a current detection coil, and issues an alarm if a disconnection is detected based on a signal from the current detection coil. An advanced camera type endoscope, characterized in that it includes an alarm device. 2. Claim 1, characterized in that the disconnection detection device includes one current detection coil that collectively surrounds each wire of the cable, and a selection switch that selectively energizes each wire in turn. The tip camera type endoscope described. 3. The disconnection detection device includes a current detection coil disposed on each line of the cable, and a selection switch that sequentially and selectively outputs a signal from each current detection coil. The tip camera type endoscope according to claim 1. 4 A second cable connecting the solid-state image sensor and the camera control unit is provided,
The tip camera type endoscope according to claim 1, 2 or 3, characterized in that when a break in the first cable is detected, the cable is switched to the second cable. 5. The tip camera type endoscope according to claim 4, wherein the second cable is also equipped with a disconnection detection device.