JPH08160319A - Light source device for endoscope - Google Patents

Abstract

PURPOSE: To provide the light source device of an endoscope capable of easily performing illumination for observing an object which strongly moves such as a vocal cord vibrating at a high speed and an esophagus influenced by heartbeat without turning on/off a light source. CONSTITUTION: As to this light source device of the endoscope in which a diaphragm 15 changing the amount of illumination luminous flux entering a light guide 4 from the light source 11 by being rotated is arranged on an illuminating optical path between the incident end of the light guide 4 for illumination of the endoscope and the light source 11; the diaphragm 15 is synchronously rotated and driven with the movement of the object of the endoscope, so that illuminating light toward the light guide 4 from the light source 11 is alternately and repeatedly shielded and transmitted synchronously with the movement of the object.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an endoscope light source device for supplying illumination light to an illumination light guide of an endoscope.

[0002]

2. Description of the Related Art When an endoscope is used to observe a rapidly moving subject such as a vocal cord vibrating at high speed or an esophagus affected by the heartbeat, it is extremely difficult to clearly observe the image of the subject. Have difficulty.

Particularly, in a frame-sequential type electronic endoscope, since illumination lights of a plurality of colors are sequentially emitted at different times, so-called color misregistration occurs in a subject that moves rapidly, and a decent monitor image is generated. Can't get

Therefore, conventionally, when observing a subject that moves rapidly, the light source lamp blinks at a high speed in synchronization with the movement of the subject to illuminate the same moment of repetition in the movement of the subject. I was able to observe the image in that state.

In the frame-sequential type electronic endoscope, filters of a plurality of colors are sequentially inserted into and removed from the illumination optical path, and illumination and light shielding which pass through the respective color filters are repeated. The cycle is a solid-state image sensor. It is much slower than the frequency of the vocal cords because it is synchronized with the imaging of. Therefore,
It is not possible to synchronize the light blocking and light transmitting by inserting and removing the frame sequential filter with the vibration of the vocal cords.

[0006]

However, if the light source lamp is continuously blinked at a high speed, the life of the light source lamp is remarkably shortened, and the noise generated by the switching for blinking causes an adverse effect such as radio interference to the surroundings. There is a problem that affects.

Therefore, the present invention provides a vocal cord vibrating at high speed,
An object of the present invention is to provide a light source device for an endoscope, which can easily perform illumination for observing a subject having a rapid movement such as an esophagus affected by the heartbeat without blinking the light source. .

[0008]

In order to achieve the above object, a light source device for an endoscope according to the present invention comprises an illumination light path between an incident end of a light guide for illumination of the endoscope and a light source. In a light source device for an endoscope in which a diaphragm is arranged that changes the amount of illumination light flux entering the light guide from the light source by being rotated, the diaphragm is rotated in synchronization with the movement of the subject of the endoscope. It is characterized in that the light source is driven to block and transmit the illumination light from the light source toward the light guide, alternately in synchronism with the movement of the subject.

The endoscope is a frame-sequential electronic endoscope, and a rotary filter for inserting and removing filters of a plurality of colors in order in the illumination optical path is provided between the light guide and the light source. May be arranged in the illumination optical path, and while the respective color filters are in the illumination optical path, light blocking and light transmission by the diaphragm may be repeatedly performed a plurality of times.

Further, a normal mode in which the diaphragm is stopped at a desired position to adjust the amount of illumination light flux incident on the light guide, and the diaphragm is continuously rotated in synchronization with the movement of the subject of the endoscope. The driving strobe mode may be switchable, and cooling fins for cooling the inside of the light source device may be provided in the diaphragm.

[0011]

Embodiments will be described with reference to the drawings. In FIG. 1, reference numeral 1 is an electronic endoscope in which a solid-state imaging device 2 made of, for example, a CCD (charge coupled device) is built in at the tip of the insertion portion.

Objective optical system 3 provided at the tip of the insertion portion
The image of the subject formed in 1 is converted into an electric signal by the solid-state image sensor 2 and transmitted, and the subject is illuminated by the illumination light transmitted through the illumination light guide fiber bundle 4.

Reference numeral 10 denotes a light guide fiber bundle 4
Is a light source device and a video processor in which a light source lamp 11 for emitting illumination light to be incident on and a video signal processing circuit 12 for controlling input / output signals to / from the solid-state imaging device 2 are incorporated. A television monitor 20 for displaying an endoscopic observation image is connected to the output end of the video signal processing circuit 12.

When the connector 5 of the endoscope 1 is connected to the light source device 10, the signal line of the solid-state image pickup device 2 is connected to the video signal processing circuit 12, and the incident end face 4a of the light guide fiber bundle 4 is connected to the light source lamp. It is set to the convergence position of the illumination light emitted from 11.

In the illumination optical path between the incident end surface 4a of the light guide fiber bundle 4 and the light source lamp 11, a three-color rotary filter 13 and a diaphragm 15 are arranged. The three-color rotary filter 13 is rotationally driven at a constant speed by the motor 14, and the three color filters of red (R), green (G), and blue (B) are synchronized with the image pickup operation of the solid-state image pickup device 2 and the optical path. It is inserted and removed.

The diaphragm 15 is formed by bending a thin metal plate into a U-shape.
It can be continuously rotated around 5a, and can be stationary in any direction.

If the diaphragm 15 is directed parallel to the illumination light emitted from the light source lamp 11 as shown in FIG. 2, the illumination light is incident on the light guide fiber bundle 4 without being blocked by the diaphragm 15.

On the other hand, as shown in FIG. 3, when the diaphragm 15 is oriented at right angles to the illumination light, the illumination light directed to the light guide fiber bundle 4 is completely blocked by the diaphragm 15.
Therefore, by stopping the diaphragm 15 in the direction between the two states, the amount of light flux incident on the light guide fiber bundle 4 can be arbitrarily controlled.

As shown in each of FIGS. 1 to 3,
The fins 17 are integrally projectingly provided on the side surface of the diaphragm 15, and when the diaphragm 15 is continuously rotated, the fins 1
Airflow is generated by 7 and is used for cooling the light source lamp 11 and the three-color rotary filter 13 in the light source device 10.

Returning to FIG. 1, the diaphragm control circuit 18 for controlling the operation of the motor 16 for driving the diaphragm, the normal mode in which the diaphragm 15 is stopped at an arbitrary position in response to a selection signal from the mode selection switch 19, and the diaphragm 15 are selected. It is possible to switch between strobe mode, which continuously rotates in synchronization with the movement of the subject.

FIG. 4 shows the configuration of the aperture control circuit 18. When the mode selection switch 19 causes the changeover switch 181 to be in the normal mode side, the first motor control circuit 182 causes the video signal processing circuit 12 to operate. The direction of the diaphragm 15 is controlled so that the brightness of the image according to the image signal input from is always constant.

When the changeover switch 181 is in the strobe mode, first, the sync detection circuit 183 detects a sync signal which is synchronized with the motion of the subject from the input video signal, and the second motor is synchronized with the sync signal. The control circuit 184 controls the diaphragm 15 to rotate continuously at a constant speed.

As a result, in the normal mode, as shown in FIG. 5, the aperture stop 1 is used unless the brightness of the subject changes.
The amount of illumination light flux passing through 5 is constant, and each time each color filter of the three-color rotation filter 13 is inserted in the illumination optical path,
The illumination light of that color enters the light guide fiber bundle 4.

On the other hand, in the strobe mode, since the diaphragm 15 continuously rotates in synchronization with the movement of the subject (for example, vocal cord vibration), as shown in FIG. Is repeated alternately in synchronism with the movement of, and the maximum amount of illumination light is transmitted each time the subject is in the same state.

Then, since the transmitted light passes through the three-color rotation filter 13 next time, while each color filter of the three-color rotation filter 13 is inserted in the illumination light path, each stop 15 makes a plurality of times (several times or several times). The light is transmitted and shielded several tens of times, and the illumination light having the strobe effect enters the light guide fiber bundle 4.

[0026]

According to the present invention, the diaphragm is rotationally driven in synchronism with the movement of the subject, and the blocking and transmission of illumination light from the light source toward the light guide are alternately repeated in synchronism with the movement of the subject. Therefore, it is possible to perform illumination for observing a fast-moving subject such as a vocal cord vibrating at high speed or an esophagus affected by the heartbeat without blinking the light source. Therefore, it is possible to easily obtain the illumination having the strobe effect without shortening the life of the light source and without causing the switching noise.

Further, by switching between the normal mode and the strobe mode, the strobe effect as described above can be obtained by rotating the diaphragm for controlling the luminous flux, so that an extra component is required. It can be constructed at low cost. Further, by providing the fins on the diaphragm, it is possible to cool the inside of the light source device and help prevent deterioration of the device due to heat.

[Brief description of drawings]

FIG. 1 is a block diagram showing a configuration of an exemplary embodiment of the present invention.

FIG. 2 is a perspective view for explaining the operation of the diaphragm of the embodiment.

FIG. 3 is a perspective view for explaining the operation of the diaphragm of the embodiment.

FIG. 4 is a block diagram of an aperture control circuit according to an embodiment.

FIG. 5 is a time chart diagram for explaining the operation of the embodiment.

FIG. 6 is a time chart diagram for explaining the operation of the embodiment.

[Explanation of Codes] 4 Light Guide Fiber Bundle 11 Light Source Lamp 15 Aperture 18 Aperture Control Circuit

Claims (4)

[Claims] 1. An aperture stop is disposed in an illumination optical path between an incident end of a light guide for illumination of an endoscope and a light source, the diaphragm being rotated so as to change the amount of illumination light flux incident on the light guide from the light source. In the endoscope light source device described above, the diaphragm is rotationally driven in synchronism with the movement of the subject of the endoscope, and the blocking and transmission of the illumination light from the light source to the light guide is the subject. A light source device for an endoscope characterized in that the light source device is alternately repeated in synchronism with the movement of the. 2. The endoscope is a frame-sequential electronic endoscope, and a rotary filter for sequentially inserting and removing filters of a plurality of colors in the illumination optical path is provided between the light guide and the light source. 2. The light source device for an endoscope according to claim 1, wherein said light source device for an endoscope is arranged in the illumination optical path, and while the respective color filters are in the illumination optical path, light blocking and light transmission by the diaphragm are repeated a plurality of times. 3. A normal mode in which the diaphragm is stopped at a desired position to adjust the amount of illumination light flux incident on the light guide, and the diaphragm is continuously rotated in synchronization with the movement of a subject of the endoscope. 3. The light source device for an endoscope according to claim 1, wherein the strobe mode to be driven can be switched. 4. The light source device for an endoscope according to claim 1, 2 or 3, wherein the diaphragm is provided with cooling fins for cooling the inside of the light source device.