JPH09164116A - Light source device for surface sequential type endoscope - Google Patents

Abstract

PROBLEM TO BE SOLVED: To connect different optical output type electronic endoscopes to the same light source. SOLUTION: A color wheel 7 formed of color filters is independently rotated within a predetermined shading range to perform the irradiation with A-type optical output type RGB light. A shading plate 12 for shading a part of the respective color filters is provided to the color wheel 7 and a clutch mechanism is provided in order to connect the shading plate 12 and the color wheel 7. That is, the tooth like projections 19 of the clutch plate 12 on the side of the shading plate 12 are meshed with an engaging grooves 21 on the side of the color wheel 7 by using a solenoid 23 and the shading plate 12 is fixed to the color wheel 7 so as to become a B-type shading range. Whereupon, the shading plate 12 is integrally rotated along with the color wheel 7 and light irradiation can be performed within a B-type optical output type shading range.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a light source device for a field-sequential endoscope, and more particularly to an electronic endoscope for sequentially irradiating light of a plurality of colors into an object to be observed, which is of a type in which the irradiation light has a different output format. The present invention relates to a light source device used in a device that can be connected.

[0002]

2. Description of the Related Art A frame-sequential endoscope system (electronic endoscope system)
Is, for example, red (R), green (G), and blue (B) color lights are sequentially irradiated from the tip to the inside of the object to be observed, and a CCD (Charge Coupled Device) is obtained based on these light irradiations. A color image can be obtained by combining the R, G, and B image signals. In a light source device used for this kind of electronic endoscope, a color wheel having color filters of respective colors is arranged in front of the light source, and R, G, B are rotated by driving the color wheel.
Each color light is sequentially output through a light guide or the like.

[0003]

However, in the conventional frame-sequential type electronic endoscope apparatus, there are electronic endoscopes (scopes) having different output formats of the R, G, and B color lights. However, there is a problem in that the electronic endoscope cannot be used by connecting it to the same main body device. In FIG.
The control states of two types of optical output and memory input (transfer) with different specifications are shown, and FIGS.
The types, FIGS. (C) and (D), are of the B type. That is, in the A type electronic endoscope, as shown in FIG. 7A, the R, G, and B color lights are sequentially output in the period t _A1 ,
A light blocking period t _A2 is set between the outputs of the respective color lights. Then, in the light-shielding period t _A2 , as shown in FIG. 6B, a memory input (transfer) control signal S1 is formed, and the pixel signal accumulated in the CCD is converted into a video signal by the control signal S1. Taken out.

Further, in the B type electronic endoscope, as shown in FIG. 2C, the R, G, and B color lights are emitted for the period t.
_B1 is sequentially output, and a light-shielding period t is provided between these color lights.
_B2 is set. Then, during the light-shielding period t _B2 , the memory input (transfer) control signal S2 is formed as shown in FIG.

The difference between the light-shielding periods t _A2 and t _B2 as described above is caused by the difference in the signal transfer configuration of the CCD, which is the image pickup element, and the like. When using electronic endoscopes having different specifications, It is necessary to change it according to the specifications. However, in the conventional light source device for an endoscope, the light-shielding period cannot be freely changed, and electronic endoscopes having different light output types cannot be connected to the same light source device.

The present invention has been made in view of the above points, and an object thereof is to form and output a plurality of colors of light having different light-shielding periods, and an electronic endoscope of a type having a different light output format. It is an object of the present invention to provide a light source device for a field-sequential endoscope, which is capable of being connected to the same device.

[0007]

In order to achieve the above object, the invention according to the first aspect of the present invention provides a light source for a surface-sequential endoscope for sequentially outputting light of a plurality of colors obtained through a plurality of color filters. In the device, color filters of a plurality of colors are formed so as to sandwich a light-shielding range of a predetermined angle between them so as to match one type of the light output format for outputting the above-mentioned light of a plurality of colors, and rotate about a wheel axis. A color wheel, a driving means for rotating the color wheel, and a part of the color filter of the color wheel are shielded from light so as to have a light-shielding range according to another type (a plurality of types) of the light output format. When a light shielding plate for and other type of the light output format is selected, the light shielding plate is fixed in a state of shielding a part of the color filter,
A clutch mechanism for connecting the light shielding plate to the color wheel so as to rotate coaxially and integrally with the wheel shaft is provided, and endoscopes of different light output types can be connected. According to a second aspect of the present invention, when the color wheel is driven independently, a light shielding plate fixing means for fixing the light shielding plate is provided at a position where the light transmitting portion of the light shielding plate is arranged in the light source optical path. Is characterized by.

According to the action invention of the first aspect, wherein, first, the optical output format is one type, for example, when connecting the A type of an electronic endoscope (the scope) in the light source apparatus, the solenoid or the like With the clutch mechanism disconnected, the light shield plate is fixed in place and only the color wheel rotates. This color wheel has, for example, R (red),
Since the G (green) and B (blue) color filters are formed within the range of a predetermined angle with the A type light shielding range, the R, G, and B lights from the light source device are provided for each A type light shielding period. Will be sequentially output for a predetermined period.

On the other hand, when connecting a scope having a different light output format, for example, a B type scope, to the light source device, the clutch mechanism is brought into a connected state by a solenoid or the like, so that it is integrated with the color wheel. The light shield rotates. Then, the light shielding plate shields part of the color filter, and R, G, and B lights are output during the B type light shielding period. In this way, by using the light-shielding plate that changes the light-shielding period, it becomes possible to connect scopes of different light output types to the light source device.

According to the second aspect of the invention, when the clutch mechanism is released, the light shielding plate is automatically fixed so that the light transmitting portion thereof is disposed in the light source optical path. Therefore, the light shielding plate that does not operate does not block the optical path.

[0011]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS FIG. 1 shows the internal structure of a light source device for a field-sequential endoscope according to an embodiment. In the figure, a xenon lamp 1 that serves as a light source is provided at a predetermined position inside the light source device, and a condenser lens 2 that collects the light emitted from the xenon lamp 1 is provided in front of the xenon lamp 1. There is. A light guide 3 for transmitting the light condensed by the condenser lens 2 is arranged in front of the condenser lens 2. That is, the light guide 3 is arranged so as to project from the end of the connector 5 on the side of the electronic endoscope (hereinafter referred to as a scope) 4, and when the connector 5 is connected to the light source device, The end portion is arranged at the condensing position of the condenser lens 2.

The light guide 3 has a scope 4
Of the image pickup device, and a CCD (Charge Coupled Device) 6, which is an image pickup device, is provided at the front end portion thereof. Therefore, the light guide 3 can illuminate the light source light, and the image light of the observed object at that time is CC.
It is captured by D6 and converted into an image signal. Furthermore,
Although not shown, the CCD 6 is connected to a processor circuit via a signal cable or the like, and the image signal transmitted from the CCD 6 is processed by this processor circuit and output to a monitor or the like. Although the processor circuit is often arranged as a separate device, it may be arranged in the light source device or in the scope.

In such a light source device, R, G, and B to be described later are provided between the condenser lens 2 and the light guide 3.
The color wheel 7 having the color filter of is arranged. A wheel shaft 8 of the color wheel 7 is supported by a bearing 9 and is connected to a motor 11 via a belt 10, and the motor 11 allows the color wheel 7 to rotate. Further, a light shielding plate 12 is arranged between the color wheel 7 and the condenser lens 2,
The shaft 13 of the light shielding plate 12 is inserted into the wheel shaft 8 of the color wheel 7 and supported by the bearing 14.

FIG. 2 shows the structures of the color wheel 7 [FIG. (A)] and the light shielding plate 12 [FIG. (B)]. As shown in the figure, the color wheel 7 includes red (R), green (G), and blue (B) color filters 15, 1.
6, 17 are formed on the concentric circle of the wheel shaft 8 in the same angular range. In addition, the color filters 15 and 1
Nos. 6 and 17 are formed so as to sandwich a light-shielding range of a predetermined angle α, and in this example, the predetermined angle α is all set so as to match the light-shielding range of the type A light output format. It is set to 20 degrees.

Further, on the light-shielding plate 12, light-shielding blades 12A having an angle β (arbitrary) sandwich the light-transmitting portion 12B.
Individually formed. In this example, the B type light shielding angle as another type is about 60 degrees (γ), and the angle β of the light shielding blade 12A is slightly smaller than 60 degrees. That is, this angle β is the same as the color wheel 7
The angle α may be set to about 40 degrees using the light-shielding range, but in the case of the example, about 60 degrees is set to about 60 degrees to
The light blocking range of 80 degrees can be set. When the A-type scope 4 is used, it is preferable to fix the light shielding plate 12 so that the light transmitting portion 12B of the light shielding plate 12 is set at a position that secures the optical path region 100. For fixation, three permanent magnets 18 with the S pole facing outward are provided on the inner peripheral portion of the light shielding plate 12 (details will be described later).

In FIG. 1, the shaft 1 of the light shielding plate 12 described above is used.
3, a clutch plate 20 having a tooth-shaped projection 19 is provided, and the clutch plate 20 is arranged in a connecting portion space formed in the wheel shaft 8. On the other hand, the connecting portion of the wheel shaft 8 is provided with an abutting surface 22 having a locking groove 21 for locking the tooth-shaped projection 19. That is, as shown in FIG. 3, the upper surface of the tooth-shaped projection 19 of the clutch plate 20 is a spiral taper surface, and the locking groove 21 of one abutting surface 22 also has the tooth-shaped projection 19. The grooves have the same shape. Therefore, when the color wheel 7 is rotated in the direction of the arrow in the figure, the tooth-like projections 19 are gradually meshed with the locking grooves 21, whereby the light shielding plate 12 is connected to the color wheel 7.

Further, drive shafts 25 and 26 projecting from the solenoids 23 and 24 are in point contact with the end of the shaft 13 of the light shielding plate 12 so as to connect and disconnect the clutch mechanism. The shaft 13 is pressed by the shafts 25 and 26 to move. A guide portion 28 for guiding the shaft 13 is provided on the rear side of the light shielding plate 12.

FIG. 4 shows the structure of the guide portion 28. The guide portion 28 is provided with three electromagnets 29, and these electromagnets 29 serve as fixing means for fixing the light shielding plate 12 when an A type scope is used. That is, this electromagnet 29 is
The light-shielding plate 1 is set so that the contact surface with
It is arranged so as to correspond to the arrangement of the S-pole permanent magnet 18 provided on the No. 2 side. Therefore, when the electromagnet 29 is energized, the N pole of the electromagnet 29 and the permanent magnet 18 of the light shielding plate 12 are
The S poles of are attracted to each other, and the light shielding plate 12 is fixed at a position that does not interfere with the optical path region 100.

Further, as shown in FIG. 1, a control circuit 30 is provided to control the motor 11, the solenoids 23 and 24, and the electromagnet 29. The control circuit 30 automatically detects the type of optical output format from the identification information (ID information) of the scope 4. That is, by utilizing the identification information conventionally given to the scope 4 or newly giving specific identification information indicating the type of the optical output format to the scope 4, this identification information can be obtained, for example, between control circuits. It can be received by communication (or may be obtained via the processor unit). In this example, it is detected whether the scope 4 is of A type or B type.

This example is constructed as described above, and its operation will be described below with reference to FIGS. In FIG.
The light path from the light source to the light guide is shown in FIG.
Shows a situation in which light is blocked by a light blocking plate in the color wheel. FIG. 7A is a diagram of type A, FIG. 7B is a diagram of type B, and FIG. . First, in FIG. 1, when the scope 4 is connected to the light source device (which is also connected to a separate processor device if present), the control circuit 30 inputs identification information from the scope 4, and the identification information is input. Based on the information, it is determined whether the light output format is A type or B type. Further, the control circuit 30 is currently aware of which type of operation state, and in consideration of this operation state, the control suitable for each type will be executed.

That is, in the B type setting state at present,
When it is determined that the connected scope 4 is of type A, the color wheel 7 is driven at low rotation or stopped to release the clutch. Then, the shaft 13 of the light shielding plate 12 is pressed and moved by the solenoid 24 via the drive shaft 26, and at the same time, the electromagnet 29 on the guide portion 28 side is energized to attract the permanent magnet 18 on the light shielding plate 12 side. Is fixed in place. Thus, FIG.
As shown in, the clutch mechanism is released, and the color wheel 7 rotates independently of the light shielding plate 12.

At this time, as shown in FIG. 5, the light output from the xenon lamp 1 passes through the light transmitting portion 12B of the light shielding plate 12 via the condenser lens 2, and the color of the color wheel 7 is changed. Filters 15, 16, 1
Reach any of 7. This state is shown in FIG. 6 (A). In the figure, light is transmitted through the R color filter 15 in the optical path range 100, but in this state the color wheel 12 rotates (in the direction of the arrow). By rotating), R, G, B lights are sequentially obtained. Then, the R, G, shielding period B light in this case would be set by the shaded range of about 20 degrees (angle alpha), as a result, as shown in FIG. 8, the output period t _A1, shielding Type A light irradiation for the period tA ₂ is performed.

On the other hand, in the setting state of FIG. 1, when it is determined that the connected scope 4 is of the B type, the color wheel 7 is driven or stopped at a low speed to connect the clutch, and the guide is guided. The energization of the electromagnet 29 on the part 28 side is stopped, and the fixation of the light shielding plate 12 is released. Then, as shown in FIG. 7, the shaft 13 of the light shielding plate 12 is pressed and moved by the solenoid 23 via the drive shaft 25, and the clutch plate 20 comes into contact with the contact surface 22. Next, when the color wheel 7 is rotationally driven, the tooth-shaped projections 19 are engaged with the locking grooves 21, so that the light shielding plate 12 is connected to the color wheel 7. In this way, as shown in FIG. 7, the clutch mechanism is in the connected state,
The color wheel 7 rotates integrally with the light shield plate 12.

This state is shown in FIG. 6 (B), and the shading plate 12 is superposed on a predetermined position of the color wheel 7 and rotates together, whereby the shading of 60 degrees (angle γ) is achieved. Range is secured. As a result, as shown in FIG. 8, it is possible to irradiate B-type R, G, and B lights having the output period t _B1 and the light-shielding period t _B2 .

In the above example, the clutch mechanism is of the type in which the connecting portion is arranged within the wheel shaft, but it is also possible to employ another clutch mechanism. For example,
By providing a projection on the front surface of the light-shield plate 12 and providing a groove of the same shape as the above-mentioned projection on the surface of the color wheel 7 facing this surface, a connecting portion is arranged between the light-shield plate 12 and the color wheel 7. A configuration can be adopted.

In the above embodiment, the light output format is automatically changed based on the identification information, but it is also possible to dispose the changeover operation switch on the operation portion and manually switch and select the light output format.

[0027]

As described above, according to the invention described in the first aspect, the color wheel having the color filter formed in the light-shielding range according to one type of the light output format is provided with the above-mentioned color filter. Since a light shield plate for shielding a part of the light is provided, the color wheel is independently rotated, and a clutch mechanism is provided to connect the light shield plate and the color wheel integrally with each other, a plurality of types are provided. It is possible to realize the light irradiation according to the light output format. Therefore, it becomes possible to connect and use an electronic endoscope of a different light output type to the light source device.

According to the second aspect of the invention, when the color wheel is driven independently, the shading plate fixing means for fixing the shading plate is provided at the position where the light transmitting portion of the shading plate is arranged in the light source optical path. Since the light shielding plate is provided, the light shielding plate is automatically positioned, and it is possible to prevent an unused light shielding plate from blocking the optical path.

[Brief description of the drawings]

FIG. 1 is a plan view showing an internal configuration of a light source device for a frame-sequential endoscope according to an embodiment of the present invention.

FIG. 2 is a diagram showing a configuration of a color wheel [FIG. (A)] and a light shielding plate [FIG. (B)] of the apparatus of FIG.

FIG. 3 is an explanatory view showing a connecting portion of a clutch mechanism of the apparatus of FIG.

FIG. 4 is a view showing a connection surface with a light shielding plate in a guide portion of the apparatus of FIG.

5 is an explanatory diagram illustrating an optical path from a light source to a light guide of the device of FIG.

6A and 6B show a light shielding state set by a light shielding plate in the color wheel of the apparatus of FIG. 1, FIG. 6A being a type A and FIG.

7 is a plan view showing an operating state when a B type electronic endoscope is connected to the apparatus of FIG. 1. FIG.

FIG. 8 is an explanatory diagram showing control states of two types of optical output and memory input having different specifications in the conventional frame-sequential endoscope apparatus.

[Explanation of symbols]

 4 ... Scope (electronic endoscope), 7 ... Color wheel, 11 ... Motor, 12 ... Shading plate, 15, 16, 17 ... Color filter, 18 ... Permanent magnet, 19 ... Teeth, 20 ... Clutch plate, 21 ... Locking groove, 22 ... Contact surface, 23, 24 ... Solenoid, 29 ... Electromagnet, 30 ... Control circuit.

Claims (2)

[Claims] 1. A light source device for a field-sequential endoscope, which sequentially outputs light of a plurality of colors obtained through a plurality of color filters, is adapted to one type of the light output format for outputting the light of the plurality of colors. As described above, color filters of a plurality of colors are formed while sandwiching a light-shielding range of a predetermined angle therebetween, a color wheel that rotates around a wheel axis, a driving unit that rotationally drives the color wheel, and the other light output formats described above. When a light-shielding plate for shielding a part of the color filter of the color wheel and another type of the light output format are selected so that the light-shielding range matches the type of A clutch for fixing a part of the color filter in a light-shielding state and connecting the light-shielding plate to the color wheel so as to rotate coaxially and integrally with the wheel shaft. And structure, the provided field sequential expressions endoscope light source device is characterized in that the connectable endoscopes of different light output formats. 2. A light-shielding plate fixing means for fixing the light-shielding plate is provided at a position where the light-transmitting portion of the light-shielding plate is arranged in the light source optical path when the color wheel is driven independently. The light source device for a frame-sequential endoscope according to claim 1.