JPH02271821A - Laser endoscope device - Google Patents

Abstract

PURPOSE:To prevent the generation of smearing of a solid-state image pickup element by providing a laser device for outputting large output laser light and small output laser light, an endoscope provided with an image pickup means, and a control means for stopping or attenuating an emission of the small output laser light. CONSTITUTION:An optical fiber 13 is inserted through the inside of a channel 18, and the laser light of a sub-laser 12 passes through a lens 22, a mirror 23, a half mirror 19 and a lens 20, and emitted from the optical fiber 13. The laser light is radiated only in a red illumination period, and its reflected light is photodetected in a CCD 6 by an objective lens 16, brought to photoelectric conversion, and as for a signal charge accumulated in each illumination period, readout is executed in an illumination stop period. Subsequently, together with a signal of a part brought to image pickup under illumination light of red, green and blue, a part irradiated with the sub-laser 12 is displayed as a red spot. When a foot switch 36 is stepped on after confirming a position irradiated with the sub-laser 12, its irradiated position is irradiated with a laser light of a large output of a main laser 14. In such a way, since the sub-laser 12 emits no light in the irradiation period, smearing can be prevented.

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial Application Field] The present invention relates to a laser endoscope system that outputs high-output laser light outside the visible range.

[Prior art] In recent years, by inserting an elongated insertion section into a body cavity,
Optical endoscopes, which can diagnose and observe target areas within the body without requiring incisions, have become widely used.

Recently, a solid-state imaging device such as a charge-coupled device is disposed on the focal plane of the objective optical system without providing an optical image transmission means, and the solid-state imaging device photoelectrically converts the optical image to generate an electrical signal. It is an electronic system that can display an image of the target area on a monitor screen by transmitting the signal and processing the signal with a signal processing device. J'! &ll has been put into practical use.

The endoscope described above can perform therapeutic treatment on a lesion by using a treatment instrument within the treatment instrument channel.

Incidentally, a YAG laser, which is a solid-state laser, is widely used as a device for performing therapeutic treatments such as hemostasis using laser light by inserting an optical fiber for transmitting laser light into the treatment instrument channel.

The oscillation wavelength of this YAG laser is 1.06 μm, which is in the far-infrared region with a longer wavelength than the visible light region, so it cannot normally be visually recognized.

Therefore, a He--Ne laser that outputs red light in the visible range is used as a guide light in the film as a sub-laser device for guiding.

[Problems to be Solved by the Invention] When a field-sequential imaging means is used as the endoscope, the illumination means sequentially and periodically irradiates the subject with red, green, and blue illumination light. A signal is read out from the imaging means in synchronization with the image capturing means, and the signal is processed to display the subject image on the display screen.

In other words, signals captured under red, green, and helmet illumination lights are sequentially read out and processed to produce color signals R and G.

These color signals R, G, and B are displayed.

However, in the conventional device, as a guide light) le-Ne
When using a line transfer type imaging device, no matter what timing you read out the signal from this imaging device, the He-Ne laser or other laser beam will always emit the original laser beam. Not only does the laser light get mixed into the R, G, and B color signals, reducing color reproducibility, but the laser light is also emitted during the period when the illumination is stopped and signals from the imaging means are being read out. However, there was a problem in that smearing occurred on the CCD and the image quality deteriorated.

For example, US Pat. No. 4,589.404 discloses a laser endoscope equipped with a fiber for transmitting laser light, but the above problem occurs because the timing of laser light irradiation is not controlled.

The present invention has been made in view of the above-mentioned points, and an object of the present invention is to provide an intra-laser mirror device that can prevent smearing from occurring in a solid-state image sensor and can be visually recognized.

Means and action for solving problem E] Inside the laser as shown in Fig. 1? J! In the mirror device 1, a light guide 3 of an electronic endoscope 2 equipped with a field-sequential imaging means is supplied with field-sequential light from a light source 4, and a living body 5 is illuminated from the distal end surface.
DA will be issued for the. The light reflected by the living body 5 is photoelectrically converted by a CCD 6 serving as an imaging means, and the electrical signal is input to a signal processing section 8 of a video processor 7, converted to a video signal, and displayed on a CRT 9.

On the other hand, the timing controller 11 of the laser device 10 receives the emission timing of the three colors of illumination light from the light source section 4, and drives the auxiliary laser (low output laser) 12 for guide light in accordance with the emission timing of these three colors. Make it emit light. This laser light is emitted to the living body 5 via the optical fiber 13, and illuminates the emission range of the main laser 14 that emits high power during treatment.

Therefore, only when three colors of illumination light are emitted, that is, the auxiliary laser 1 for guiding light between the stored fI 111 of the CCD 6
Since the CCD 6 is exposed to the second light and is not exposed during the reading period of the CCD 6, a good television image without smearing can be obtained.

[Example] Hereinafter, the present invention will be specifically explained with reference to the drawings.

2 and 3 relate to a first embodiment of the present invention, FIG. 2 shows the overall configuration of the first embodiment, and FIG. 3 shows an operational diagram.

As shown in FIG. 2, the laser endoscope device 1 of the first embodiment includes an electronic endoscope 2, a light source section 4 that supplies illumination light to the electronic endoscope 2, and a signal processing section 8 that processes signals. The video processor 7 has a built-in video processor 7, a CRT 9 that displays the video signal output from the signal processing section 8, and a laser device @10 that outputs laser light.

The electronic endoscope 2 has an elongated insertion section 15 so as to be inserted into a living body, and a light guide 3 for transmitting illumination light supplied from the light source section 4 is inserted into the insertion section 15. ing. Illumination light is emitted from the distal end surface of the light guide 3 to a target region 5' in the body cavity, etc., so that it can be illuminated.

The focal plane of the illuminated region 5' is imaged by the objective lens 16 attached to the distal end of the insertion section 15 on the disposed CCD 6. The signal photoelectrically converted by the CCD 6 is amplified by a preamplifier 17 and input to a signal processing section 8 via a signal cable, and the signal-processed image is displayed on a CRT 9.

The electronic gift 112 can be inserted with a treatment instrument (
Treatment instrument) A channel 18 is provided, into which an optical fiber 13 for transmitting laser light from the main laser 14, such as a YAG laser, can be inserted. One end of this optical fiber 18 is connected to the laser device 10.
As a result, the laser beam of the main laser 14 is supplied to the incident end face via one half mirror and the condenser lens 20.

The laser beam transmitted by this optical fiber 13 is emitted from the tip surface.

The laser 10 is provided with an auxiliary laser 12 consisting of a laser diode, which is driven by a laser diode (LD) drive circuit 21. Covers the light emission with +lJ current.

This sub-laser 12 emits a small-output laser beam. This laser beam is a red light, which is made into a parallel beam by a lens 22, reflected by a mirror 23, and guided to a half mirror 19. The laser beam reflected by -19 is condensed by a condenser lens 20 and irradiated onto the incident end face of the optical fiber 13.

The auxiliary laser 12 is controlled by a timing controller 11 so that it emits light in synchronization with the illumination of the light source section 4.

The light source section 4 irradiates white light from a lamp 25 onto the end surface of the light guide 3 through a rotating color filter 27 rotated by a motor 26 .

The rotating color filter 27 has three fan-shaped openings on a disk, and color filters 28R, 28G, and 28B that transmit red, green, and blue wavelength bands are attached to each of the rotating color filters 27. Therefore, lie [red for guide 3].

Light of each wavelength of green and blue is supplied, and this light is emitted from the distal end surface, and the target region 5' is illuminated with sequential red, green, and blue light.

The illuminated target region 5' is imaged on the CCD 6 by the objective lens 16. This COD6 is a line transfer type in which a charge storage section and a transfer section are common, and is a COD suitable for reducing the diameter of the distal end, such as in an electronic endoscope. This C
The CD 6 is read by applying drive signals from two drive circuits, and is input to the preprocessing circuit 31 via the preamplifier 17. In this process circuit 31, γ
After correction and the like, the signal is converted into a digital signal by the A/D converter 32 and stored in the memory 33. In this memory 33, signals captured under red, green, and blue illumination lights are sequentially written, and are simultaneously read out at the time of readout.
It is converted into G and B and displayed in color on a CRT9.

By the way, the light source section 4 includes a rotating color filter 27.
Each color filter 28R, 28G in.

A color filter detection means 35 is installed for detecting the rotational position of the color filters 28R, 28G, 28B.
When B is interposed in the illumination optical path, a detection signal is sent to the timing controller 11.

The color filter detection means 35 is composed of, for example, a photointerrupter, and when each color filter 28R, 28G, 28B is interposed on the illumination optical path, a detection signal as shown in FIG. 3(a) is sent to the timing controller 11. Output to.

Based on this detection signal, the timing controller 11 sends an instruction signal (control signal) to the LD drive circuit 21 to cause the sub laser 12 to emit light during the red illumination period, as shown in FIG. 3(C), for example. As shown in (d), the sub laser 12 is caused to emit light during this instruction signal period.

Note that the main laser 14 is emitted by a foot switch 36, for example.

The operation of this first embodiment will be explained below.

As shown in Figure 2, electronic endoscope t? I2 is inserted into a body cavity and set to a state where, for example, a site where hemostasis treatment is to be performed can be observed.

The optical fiber 13 is then inserted into the channel 18, with its tip facing the area where hemostasis is to be performed. Then, the laser beam of the sub laser 12 passes through the lens 22, the mirror 23,
The light enters one end of the optical fiber 13 through one half mirror and the lens 20, and is emitted from the tip. This laser light is applied only during the red illumination period, as shown in FIG. 3(d). Therefore, the reflected light is reflected by the objective lens 16.
The signal charges received by the CCD 6, photoelectrically converted, and accumulated during each illumination period are read out during the illumination stop period, as shown in FIG. 3(b).

Along with the signals of the area imaged after these red, green, and blue illumination lights, the area irradiated by the sub laser 12 is shown at C in FIG.
It is displayed as a red spot on the display screen of RT9.

In other words, since the sub laser 12 emits light only during the red illumination period, it is displayed as a red spot like this.

Once the irradiation position has been confirmed with the auxiliary laser 12, the foot switch 36 is stepped on, and the high-output laser beam of the main laser 14 is irradiated to the irradiation position.

According to this first embodiment, the sub laser 12 does not emit light during the illumination period, and therefore during the charge reading period.
There is no exposure during signal transfer, smearing can be prevented, and endoscopic R@ with good image quality can be obtained.

FIG. 4 shows a timing diagram of a second embodiment of the present invention.

In the first embodiment, the sub laser 12 is made to emit light during the red illumination period, but as shown in FIG. 4(b), the green illumination period (
(charge accumulation period), or the light may be emitted during the blue illumination period as shown in FIG.

If the light is emitted during the green illumination period, the irradiation position will be displayed in green, and if the light is emitted during the blue illumination period, it will become blue guide light.

In addition, the light may be emitted during the red, green, and blue illumination periods as shown in FIG. 4(d), or the light may be emitted during the red and green illumination periods as shown in FIG. 4(e). You can let me. Fourth
In the case of figure (d), it is displayed on the CRT as a white guide light, and in the figure (e), it is displayed as a white guide light on the CRT.
displayed above.

FIG. 5 shows a laser endoscope device 41 according to a third embodiment of the present invention.

In the first embodiment described above, a sub laser 12 separate from the main laser 14 is used for guiding light, whereas in this embodiment, a means for switching the light output of the main laser 14 to a weak level is provided, and the sub laser 12 is It is designed to serve 12 functions.

That is, a neutral density filter 42 and a shutter 43 are provided on the emission side of the main laser 14, and insertion and removal from the optical path are controlled by a filter drive circuit 44 and a shutter drive circuit 45, respectively. These drive circuits 44 and 45 are controlled by a timing controller 11.

Further, the on/off signal of the foot switch 36 is sent to the timing controller 11, so that the timing of outputting the high output laser beam is also controlled.

In addition, in this embodiment, a CCD sensitive to the above laser beam is used.
Its characteristic is that it is 6.

The operation of this third embodiment will be explained below.

When the foot switch 36 is off as shown in FIG. 6(b), the neutral density filter 42 is interposed on the output light path (indicated by IN) as shown in FIG. 6(c). .

), and as shown in FIG. 4(d), the shutter 43 is set to open only when, for example, a red color filter 28R is interposed on the illumination optical path.

Therefore, by passing the output of the main laser 14 through the neutral density filter 42, the output power of the main laser 14 is reduced to several mW, for example, as shown in FIG. 6(e).
Pi! The laser light is supplied to the optical fiber 13 through the shutter 43 through the red color filter 2.
This is only the period when 8R is inserted in the illumination optical path.

Since the CCD 6 is sensitive to the main laser beam, it outputs a photoelectrically converted signal using the reflected light from the irradiation position.

Therefore, in this case, the target area is displayed in color on the CRT screen as shown in FIG. 5, and the position where the light is emitted from the tip end of the optical fiber 13 is displayed as a red spot.

Therefore, the user can accurately know the location,
When this spot is set at a desired position and the foot switch 36 is turned on, the neutral density filter 42 is retracted from the optical path and the shutter 43 is closed, as shown in FIG. 6(C).
is inserted and removed from the optical path in synchronization with the illumination period.

Therefore, a high-output laser beam is supplied to the optical fiber 13 as shown in FIG. 6(e), and the high-output laser beam can be irradiated to the above-mentioned set position to perform therapeutic treatments such as excision and hemostasis. It can be carried out. According to this third embodiment, YAG
By controlling the optical output of a laser in an invisible range, such as a CO2 laser, and switching between a high output state and a weak output state, it is possible to accurately confirm the irradiation position, etc. during treatment. In other words, the only difference between the guide light and the treatment light is the optical output level, so even if the optical fiber 13 is wavelength dependent, it is difficult to confirm the irradiation position during treatment. I can do it with great vigor. or,
The optical fiber 13 may be of any type as long as it has the function of transmitting the wavelength of the laser beam used.

In addition, it is not necessary to use a laser device within the visible range as a guide light, so costs can be reduced, and there is no need to newly insert the light guiding means into the insertion section, so there is no need to make the insertion section thicker. It's over.

In this third embodiment, it is clear that the timing of opening the shutter 43 may be synchronized with the illumination period for colors other than red.

Further, the present invention can also be applied to a case where a simultaneous imaging means is used in which a color separation filter is disposed in front of the COD.

In this case, if the COD is of an incline transfer type, the laser device can be driven continuously.

On the other hand, in the case of a line transfer type in which the light receiving section (charge storage section) and the transfer section are shared, if the light emission is stopped during the transfer period, as in the case of each of the above-mentioned embodiments,
Smearing can be prevented.

Note that, in order to prevent smearing, the laser light emission is not limited to stopping emission during the signal readout period, and may be attenuated. This reduced Q may be attenuated mechanically using a filter or the like, or it may be attenuated electrically, for example by changing the drive current for oscillating the laser to lower the level of the oscillation output.

As described above, according to the present invention, since the emission of at least a small output laser beam is stopped or attenuated during the signal readout period of the imaging means, the occurrence of smearing can be substantially eliminated.

[Brief explanation of drawings]

FIG. 1 is a block diagram showing the general configuration of the present invention, FIGS. 2 and 3 relate to the first embodiment of the present invention, and FIG. 2 shows the first embodiment of the present invention.
3 is a timing diagram for explaining the operation of the 5jS1 embodiment, FIG. 4 is a timing diagram for explaining the operation of the second embodiment of the present invention, and FIG. 5 is a third embodiment of the present invention. FIG. 6 is a timing chart for explaining the operation of the third embodiment. 1... Laser endoscope device 2... Electronic endoscope 3...
・Light guide 4...Light source part 6...CCD
7...Video processor 8...Signal processing section 9...CRTll...Timing controller 12...Sub-laser 13...Main laser Fig. 1

Claims (1)

[Claims] a laser device that outputs a high-power laser beam and a low-power laser beam for irradiating the same area as the high-power laser beam;
An endoscope equipped with an imaging means sensitive to at least the low-power laser beam, and a control means for stopping or attenuating emission of at least the low-power laser beam during a signal readout period from the imaging means. A laser endoscope device featuring: