JPH02287508A - Observing method by endoscope device and endoscope - Google Patents

Abstract

PURPOSE:To obtain the endoscope and observing method by which a sharp still image can be obtained even while an insert part is floating by the thrust by the injection of jet fluid by picking up the image while limiting an actual image pickup charge storage time within the range of the charge storage time of a solid-state image pickup element which image-picks up an observation visual field. CONSTITUTION:In the endoscope device which receives the thrust by the jet injection of the fluid to make the inserting part float, an object image obtained through an objective 23 atop of the inserting part is converted photoelectrically and transmitted as a photoelectrically converted signal from a CCD 22 to a control unit 21. The camera control unit 21 is provided with a system controller 28 and controls the operation of the CCD 22 through a CCD driving circuit 29 to realize a shutter function. Namely, a freeze video by the image pickup video signal of the solid-state image pickup element 22 becomes sharp by varying the charge storage time for actual image pickup operation according to the extent of the level of the output signal of the CCD 22 which is detected by a video level detector 24, thereby obtaining a blurring-free still image.

Description

[Detailed description of the invention]

[Industrial Field of Application] The present invention relates to an endoscope device in which an insertion portion is levitated by receiving thrust from a jet jet, and an observation method using the endoscope. [Prior Art] Conventionally, in Japanese Patent Application Laid-Open No. 62-251639, a jetting port is provided at the distal end portion of the insertion portion, and a jet of fluid is jetted from the injection port to cause the insertion portion to levitate using the thrust generated. A type of endoscope is known. This type of floating endoscope is often used for industrial purposes, for example, for inspecting gas pipes, tanks, or cavities within the wings of large airplanes. According to this, since the insertion section can be floated, it becomes possible to observe every corner of a high cavity. [Problems to be solved by the invention] However, in this type of floating endoscope device,
Since the insertion part is floated by a jet of jet fluid and observed while approaching the site to be inspected, the insertion part floats in a delicate balance. For this reason, the tip of the insertion tube is extremely unstable compared to the usage of a general endoscope, and it is not possible to observe in a stable state as with a general endoscope. It was normal. Therefore, in observation using this type of jet floating endoscope, it is usually difficult to obtain a stable observation image, so it has been difficult to inspect the inspection target region in more detail. On the other hand, recently, a so-called video endoscope has been put into practical use, which uses a solid-state imaging device as an imaging means and allows observation on a monitor. This type of endoscope allows for easier recording and playback of observation images than normal optical endoscopes, and also allows for a freeze operation to be used to view a still image during observation. It is possible. The method for obtaining this still image is to store the video signal, which has been accumulated in a charge accumulation time (generally t7e. seconds) in one field in the imaging CCD, in a memory means, and read it out to freeze the image. It is converted into a signal and displayed on a monitor for observation. Therefore, if the subject moves during 1160 seconds, which is the typical charge accumulation time for one field in an imaging CCD, the still image obtained will also become blurred due to the freezing. However, as mentioned above, in the endoscopic device that uses jet fluid to float the insertion part to observe the inspection area, the insertion part floats in a delicate balance, and the objective The reality is that the distal end of the insertion tube, which incorporates the optical system, sways slightly at a considerable rate. Therefore, even if you try to observe a still image caused by this freeze, the still image will be considerably blurred. However, with this jet floating endoscope device, it is difficult to observe even during normal observation due to the shaking of the insertion section, so it is rather useful to obtain still images without blur for more detailed observation. It is desirable to do so. Nevertheless, even still images obtained by freezing are blurred, and it is not possible to obtain clear still images. The present invention has been made in view of the above-mentioned problems, and its purpose is to provide an endoscope device and an internal device capable of obtaining clear still images without blurring even when the insertion section is floating due to the thrust generated by jet fluid injection. The object of the present invention is to provide an observation method using a microscope. [Means and operations for solving the problems] In order to solve the above problems, a first invention provides an endoscope apparatus in which an insertion section is levitated by receiving thrust from jetting a fluid. means for capturing an image of an observation field of view with an image sensor; a shutter means for limiting an actual charge accumulation time for imaging within a charge accumulation time of the solid-state image sensor; and a means for storing a video signal imaged by the solid-state image sensor. It consists of a video processing means that converts into a frozen video using a memory, and a freeze operation means that is operated when the video processing means obtains a frozen video. Therefore, since the solid-state image sensor that images the observation field when obtaining a frozen image limits the actual charge accumulation time for imaging within the range of its charge accumulation time, the image captured by the solid-state image sensor Frozen images caused by signals become clearer. In other words, even when the insertion tube is floating due to the thrust generated by jet fluid injection, clear still images without blur can be obtained.
Detailed observation is possible. In addition, the second invention is an observation method using an endoscope in which the insertion section is levitated by receiving a thrust generated by jetting a fluid, in which the imaging time of the imaging system is controlled and the captured video signal is This was converted into a frozen image for observation. In this invention as well, even when the insertion section is floating due to the thrust generated by jet fluid injection, a clear still image without blurring can be obtained and detailed observation can be made.

【Example】

The drawings show one embodiment of the invention. As shown in FIG. 1, the endoscope 1 in this embodiment has an insertion section 3 connected to an operation section 2, and the insertion section 3 includes a flexible tube section 4, a curved tube section 5, and a curved tube section 5 in order from the operation section 2 side. It is constructed by connecting the tip portions 6. The distal end 6 of the insertion section 3 is provided with an observation window, an illumination window, etc., like a general endoscope. Furthermore, an injection port 8 for jetting fluid such as air is provided on the lower surface of the connecting tube 7 that connects the flexible tube section 4 and the curved tube section 5. The injection port 8 is connected to an external electric light source device 12 (described later) through an air supply tube (not shown) inserted through the insertion section 3, the operating section 2, and the universal cord 11 extending from the operating section 2. It is adapted to be connected to a pressurized fluid plug (not shown) incorporated in the . Further, the operation section 2 of the endoscope 1 is provided with a flow rate control switch 13, and by operating the switch 13, the flow rate of the fluid supplied from the pressurized fluid source to the injection port 8 can be controlled. There is. Furthermore, the operating section 2 of the endoscope 1 is provided with a bending operation knob 14 for bending the bending tube section 5 . Connector 1 is attached to the extending end of the universal cord 11 mentioned above.
5 is provided, and this connector 15 connects to the electric light source device 12.
It is removably connected to. In addition to the pressurized fluid source, an illumination light source, a power source, and the like are built into the electric light source device 12. On the front of the main body of the electric light source device 12, there is a power switch 16 and a knob 1 for adjusting the amount of illumination light.
7th grade is provided. Further, a signal cable 20 is branched from the connector 15 of the universal cord 11 and connected to the signal cable 20, and a camera control unit 21 is connected to the signal cable 20. This camera control unit 21 includes a universal cord 11 and a signal cable 2.
0 to a CCD 22 which is a solid-state image sensor provided at the distal end 6 of the insertion section 3. Furthermore, this CCD
As 22, for example, an interline type is used. An object is imaged on the photosensitive surface of the CCD 22 by an objective lens 23 provided at the distal end 6 of the insertion section 3. The photoelectrically converted signal outputted from the signal output terminal of the C0D 22 is transmitted to the camera control unit 21 through the signal cable 20 and inputted to the video level detector 24 and the video processor 25. This video processor 25 takes in the input output signal of the CCD 22, converts it into a video signal of a predetermined standard such as the NTSC system, and outputs it to the TV monitor 26 side. The video level detector 24 detects the level of the output signal of the CCD 22 and converts it into a DC signal. For example, the higher the level of the output signal of the CCD 22, the higher the output signal is output as a DC voltage proportional to the level. . Further, the camera control unit 21 is provided with a system controller 28, which realizes a shutter function by controlling the operation of the CCD 22 through a CCD drive circuit 29. That is, depending on the level of the output signal of the CCD 22 detected by the video level detector 24, the CCD 2
A shutter means is provided which prohibits charge accumulation for a certain period of time by reading out the charges accumulated in the photodiode forming the photodiode 2 at high speed, and limits the actual charge accumulation time for imaging within the range of the charge accumulation time. It consists of That is, by reading out the charges accumulated in the photodiode at high speed, the charges accumulated in the photodiode are swept away, and the subsequently accumulated charges are used for actual image display. Therefore, the actual charge accumulation time for imaging is limited to a time shorter than the original charge accumulation time for imaging, so that the shutter function is achieved. Then, the CCD 2 detected by the video level detector 24
The actual imaging charge accumulation time is changed depending on the level of the second output signal. That is, when the level of the output signal of the CCD 22 is high, the accumulation time is shortened;
When the level of the output signal of the CD 22 is low, the storage time is increased. The degree of this 33 adjustment can be changed depending on the usage situation and terms, but in general, the accumulation time is kept as short as possible without causing insufficient exposure (sensitivity).
It is desirable to fully utilize the shutter function. Further, the output signal of the CCD 22 is processed into a digital signal by the video processor 25 so that it can be stored in the video memory 30. This video memory 3
For example, a field memory can be used as 0. Then, the video signal is stored in the video memory 30 by the operation signal of the freeze switch 31, and read out to display 1g of video of a predetermined standard such as the NTSC system. It is converted into a signal and output to the TV monitor 26 to obtain a still image. The still images obtained in this way are unique because they are obtained by instantaneous shooting by limiting the actual charge storage time for imaging to a shorter time than the original charge storage time for imaging of the CCD 22. Even if the insertion section 3 shakes at a considerable speed, a clear image can be obtained. In addition, this freeze switch 31
may be provided on the operating section 2 of the endoscope 1, on the front of the main body of the electric light source device 12, or on both. For example, when observing a moving image, a special mode in which the shutter function is activated to take an image and a normal mode in which the shutter function is not activated can be selected by operating a signal from a mode changeover switch 32 provided on the front of the main body of the electric light source device 12. It is possible to switch. When the mode changeover switch 32 is operated, the system controller 28 receives the operation signal and adjusts the CCD drive circuit 29 to control the CCD drive circuit 29.
By controlling the operation of 22, the shutter function is realized. Therefore, when using an endoscope apparatus having this configuration, the insertion section 3 of the endoscope 1 is introduced into the object to be examined through the inspection hole 36 formed in the wall 35 of the object to be examined. The insertion section 3 is floated by jetting pressurized air from the jet nozzle 8. Then, while observing the state inside the object to be inspected in the normal mode or special mode on the real-time monitor image displayed on the TV monitor 26 as shown in FIG. The section 6 is introduced into the inspection site A. If a still image is required for detailed inspection, the freeze switch 31 is operated. Based on this operation signal, the system controller 28 controls the operation of the CCD drive circuit 29 and activates the shutter function to take an image. In addition, the output signal of the CCD 22 is converted into a digital signal and stored in the video memory 30 of the video processor 25, and the video processor 25 further reads this and converts it into a digital signal.
The video signal is converted into a video signal of a predetermined standard such as the C format, and outputted to the TV monitor 26 to display a still image. The operator can perform a detailed examination by observing the still image thus obtained. And this still image is CCD22
Since the actual charge storage time for imaging was limited to a shorter time than the original charge storage time for imaging, and instantaneous imaging was performed, the insertion section 3 was shaken at a considerable speed during levitation. You can also obtain clear still images. Note that the still image may be recorded or photographed. Originally, with this jet floating type endoscope device, even during normal observation, it is always difficult to observe due to the shaking of the insertion section 3, so it is rather desirable to obtain a still image without blur for detailed observation. However, according to the above-mentioned shutter function, the still image obtained by freezing becomes considerably clearer than a normal still image which is blurred. Therefore, it is suitable for this type of endoscope. Note that the present invention is not limited to the above embodiments. For example, a liquid crystal shutter may be provided as the shutter means in front of the photosensitive surface of the solid-state imaging element, and the liquid crystal shutter may be opened in synchronization with the imaging operation of the solid-state imaging element when a freeze operation is performed. It may be possible to perform instantaneous imaging by limiting the actual charge accumulation time for imaging to a shorter time than the original charge accumulation time for imaging. In addition, a shutter mechanism is installed in the illumination system of the endoscope to instantaneously transmit the illumination light, and in accordance with the synchronization signal of the imaging operation of the solid-state imaging device, the original imaging charge accumulation time of the solid-state imaging device is It may also be possible to perform instantaneous imaging by irradiating the light for a short time and limiting the actual charge accumulation time for imaging. Furthermore, if a strobe light emitting means is added to the illumination means and the strobe light emitting means is made to emit light within the range of the original charge accumulation period for imaging of the above-mentioned COD, the time will be shorter than the original charge accumulation time for imaging. Since the actual charge accumulation time for imaging can be limited, the amount of exposure can be ensured in the present invention, which performs instantaneous imaging. Furthermore, it is possible to instantly capture clear images by limiting the actual charge accumulation time for imaging to a shorter time. [Effects of the Invention] As explained above, according to the present invention, a clear still image without blur can be obtained even when the insertion section is floating due to the thrust generated by jet fluid injection. In endoscope devices that levitate to observe the area to be inspected, the insertion section floats in a delicate balance, and the tip of the insertion section, which incorporates the objective optical system, moves very quickly. The reality is that the object is shaking, making it difficult to observe even in normal observation.However, according to the present invention, a clear still image without blur can be obtained and extremely detailed observation can be made.

[Brief explanation of the drawing]

The drawings show one embodiment of the present invention, with FIG. 1 being a perspective view showing the overall configuration, FIG. 2 being a diagram showing the display state of the monitor screen, and FIG. 3 schematically showing the configuration of the electrical system. FIG. 1... Endoscope, 2... Operation section, 3... Insertion section, 8
...Injection port, 21...Camera control unit, 22...CCD, 25...Video processor, 2
6... TV monitor, 28... System controller, 29... CCD drive circuit, 31... Freeze switch. Applicant's agent Patent attorney Atsushi Tsuboi

Claims (2)

[Claims] (1) In an endoscope device in which the insertion section is levitated by receiving a thrust generated by jetting a fluid, a means for capturing an image of the observation field with a solid-state image sensor and a range of charge accumulation time of the solid-state image sensor a shutter means for limiting the actual charge accumulation time for imaging; a video processing means for converting the video signal imaged by the solid-state imaging device into a frozen video using a memory for storing the video signal; and a frozen video is obtained by the video processing means. 1. An endoscope device comprising a freeze operation means that is operated at times. (2) In an observation method using an endoscope in which the insertion section is levitated by the thrust generated by jetting fluid, the imaging time of the imaging system is controlled and the captured image signal is converted into a frozen image. An observation method using an endoscope, which is characterized by observation using an endoscope.