JP2009146823A - Light source device and endoscope device equipped with the same - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a light source device which can decrease a contact thermal resistance between a substrate and a heat sink without affecting the optical property of a light guide member, and to provide an endoscope equipped with the same. <P>SOLUTION: The light source includes: the substrate; a light source which is mounted on the surface of the substrate and emits illuminating light; the light guide member which guides the illuminating light emitted from the light source; the heat sink which is arranged on the rear surface of the substrate and which absorbs and emits the heat of the substrate; a holding member which is fixed on the front surface of the substrate, which has two or more inclined planes that gradually approach one another as they get away from the front surface of the substrate, and which holds at a position opposite to the light source the light guide member; and a pressing member which applies an external force to the inclined planes of the holding member such that the component forces thereof, which are produced in the direction along the front surface of the substrate, balance each other. <P>COPYRIGHT: (C)2009,JPO&INPIT

Description

  The present invention relates to a light source device that dissipates heat generated from a light source by a radiator and an endoscope apparatus including the same.

  Since a high power LED (light emitting diode) used as a light source generates a large amount of heat, it is common to dissipate heat with a radiator. At this time, it is effective to apply a heat dissipating grease between the heat sink and the substrate on which the LED as the heating element is mounted in order to reduce the contact heat resistance. Here, the reduction effect of the contact thermal resistance due to the heat radiation grease varies depending on the pressing load, and the heat dissipation efficiency of the substrate can be improved by pressing the substrate against the radiator with a large pressing load. As a specific method, a method of applying a constant pressing load by screwing a substrate to a radiator is known (for example, see Patent Document 1).

However, in recent years, the miniaturization of LEDs has progressed, making it difficult to provide screw holes. Moreover, there is a problem that the pressing load changes due to the loosening of the screws, and the contact thermal resistance between the substrate and the radiator changes. In order to solve the above problem, a technique for fixing a light guide member with a leaf spring has been disclosed (for example, see Patent Document 2).
JP 2004-93623 A Japanese Patent Application Laid-Open No. 08-227034

  However, in the technique described in Patent Document 2, a load is directly applied to the light guide member, which may cause the light guide member to bend and affect the optical characteristics of the light guide member. On the other hand, if the load applied to the light guide member is reduced, the contact thermal resistance between the substrate and the heat sink increases, and there is a disadvantage that the heat dissipation efficiency of the substrate decreases.

  The present invention has been made in view of the above circumstances, and includes a light source device capable of reducing contact thermal resistance between a substrate and a radiator without affecting the optical characteristics of the light guide member, and the light source device. An object is to provide an endoscope apparatus.

In order to achieve the above object, the present invention employs the following means.
The present invention is arranged in contact with the back surface of the substrate, a light source attached to the surface of the substrate and emitting illumination light, a light guide member that guides the illumination light emitted from the light source, A radiator that absorbs and dissipates heat of the substrate; and has two or more inclined surfaces that are fixed to the surface side of the substrate and gradually approach each other as the distance from the surface of the substrate increases. A light source device including a holding member that holds a light guide member and a pressing member that applies an external force that balances the component forces in the direction along the surface of the substrate to the inclined surface of the holding member is employed.

  According to the present invention, when an external force is applied to the two or more inclined surfaces of the holding member by the pressing member so that component forces in the direction along the surface of the substrate are balanced, the pressing member is fixed to the holding member and the holding member. A component force is generated in the direction perpendicular to the front surface of the substrate with respect to the substrate, and the contact pressure with respect to the radiator on the back surface of the substrate is increased. As a result, the contact thermal resistance between the substrate and the radiator can be reduced without directly applying a load to the light guide member, and the heat dissipation efficiency of the substrate can be improved without affecting the optical characteristics of the light guide member. It becomes possible.

In the above invention, the position of the intersection of the normal of the inclined surface and the surface of the substrate at the point of application of the external force applied by the pressing member is within the range of the contact surface between the holding member and the substrate. May be.
By doing so, it is possible to prevent the holding member from being bent and to prevent the positional relationship between the light guide member held by the holding member and the light source from being changed.

In the above invention, an angle formed between the inclined surface and the surface of the substrate may be 45 ° or less.
By doing in this way, the component force which acts on the direction orthogonal to the surface of a board | substrate can be enlarged, and it becomes possible to reduce the load added to a holding member by a press member. Thereby, the deflection of the holding member can be prevented.

In the above invention, the radiator is formed in a substantially cylindrical shape, and the light source, the light guide member, the holding member, and the substrate are arranged on the inner surface side of the radiator with an optical axis toward the center in the circumferential direction. A plurality of reflectors arranged at intervals, including a reflecting member that reflects the illumination light emitted from the light source and guided by the light guide member in the axial direction of the radiator, and the pressing member is formed in an annular shape And it may be made to fix to the inner surface side of the radiator so that a plurality of the holding members may be sandwiched simultaneously from the outside in the axial direction of the radiator.
By doing in this way, a plurality of holding members are held by the external force applied to the inclined surface of the holding member by simultaneously sandwiching a plurality of holding members arranged on the inner surface side of the radiator from the outside in the axial direction of the radiator. Each of the fixed substrates can be fixed so as to be pressed against a radially outward radiator. Thereby, a pressing member can be shared with respect to a plurality of holding members, the number of parts can be reduced, and the attaching operation of the pressing member can be facilitated. Moreover, the external force applied to the inclined surface of each holding member can be made substantially uniform, and the force for pressing the back surface of the substrate against the radiator can be made substantially uniform. As a result, the heat dissipation efficiency of each light source can be made equal, and the amount of illumination light emitted from each light source can be made uniform.
Here, the illumination light emitted from each light source is guided by a light guide member disposed toward the center of the radiator formed in a substantially cylindrical shape, and reflected by the reflecting member in the axial direction of the radiator. . Therefore, it is possible to continuously irradiate stable illumination light by making the amount of illumination light emitted from each light source uniform.

In the above invention, there is provided fastening means for moving the pressing member in the axial direction of the radiator by rotating the pressing member around the axis of the radiator with respect to the holding member, and the pressing member and the An annular sliding member that slides the pressing member may be sandwiched between the holding member.
By doing so, the pressing member can be easily moved in the axial direction of the radiator by rotating the pressing member around the axis of the radiator with respect to the holding member by the fastening means. As specific fastening means, for example, the heat sink may be subjected to female screw processing, and the male screw processing of a size corresponding to the female screw may be performed on the outer peripheral portion of the pressing member.
In addition, since the annular sliding member that slides the pressing member is sandwiched between the pressing member and the holding member, it prevents the rotational torque when the pressing member is rotated from being applied to the holding member. be able to. As a specific sliding member, for example, an annular member such as a washer may be used, and by providing an elastic body such as rubber on the sliding member, dimensional tolerances such as a pressing member and a holding member can be absorbed. It becomes possible.

The present invention is an endoscope apparatus including the above-described light source device, the imaging device acquiring an image of an observation site irradiated with illumination light guided by the light guide member, and the imaging device An endoscope apparatus including a video signal processing unit that performs at least color conversion processing on a video signal and a display monitor that displays an image subjected to image processing by the video signal processing unit is employed.
According to the present invention, stable illumination light can be emitted, and the image quality of a video signal to be acquired can be improved.

  According to the present invention, it is possible to reduce the contact thermal resistance between the substrate and the radiator without affecting the optical characteristics of the light guide member.

[First Embodiment]
The light source device according to the first embodiment of the present invention will be described below with reference to the drawings.
As shown in FIG. 1, the light source device 1 according to the present embodiment absorbs heat from the substrate 13, the light source 11 that emits illumination light, the light guide member 12 that guides illumination light, and the substrate 13. A radiator 14 to be diffused, a holding member 15 that holds the light guide member 12 at a position facing the light source 11, and a pressing member 16 that applies an external force to the holding member 15 are provided.

The light source 11 is a light emitting element such as a high-intensity LED, for example, and has a property of generating heat during light emission.
The light guide unit 12 is, for example, a light-transmitting rod made of glass or polycarbonate, and is provided to face the light source 11 so as to guide illumination light. The light guide unit 12 includes an incident end 21 on which illumination light from the light source 11 is incident, an exit end 22 having a larger area than the incident end 21, and an exit end 22 while reflecting the illumination light incident from the incident end 21. And a reflecting surface 23 that guides the light. Thus, by providing the reflective surface 23 with a taper, the directivity of the illumination light is improved.

The substrate 13 has a light source 11 attached to the front surface, and conducts heat generated by the light source 11 to the back surface.
The radiator 14 is, for example, an air-cooled radiator having a plurality of radiation fins, and is disposed in contact with the back surface of the substrate 13. A heat radiation grease 25 is applied between the substrate 13 and the heat radiator 14 in order to improve heat radiation efficiency. The heat radiator 14 absorbs the heat of the substrate 13 through the heat radiation grease 25 and absorbs the absorbed heat. Is dissipated from the radiating fin.

  The holding member 15 is fixed to the surface side of the substrate 13, and holds the incident end 21 of the light guide member 12 at a position facing the light source 11. The holding member 15 has two or more inclined surfaces 31 that gradually approach each other as the distance from the surface of the substrate 13 increases. That is, the holding member 15 has a shape that tapers as the distance from the surface of the substrate 13 increases.

The pressing member 16 applies an external force to the inclined surface 31 of the holding member 15 so that the component forces in the direction along the substrate 13 are balanced. That is, in FIG. 1, when the external forces applied by the pressing member 16 a and the pressing member 16 b provided as a pair are F _a and F _b , the external forces F _a and F _b are components Q _{a in the} direction along the inclined surface 31. , and _{Q b,} the normal direction of the component _P a of the inclined surface 31, can be divided into a _{P b,} the component force in the direction _{P a1} along the surface of the substrate 13 for component _{P a,} for component _{P b} a component force P _b1 direction along the surface of the substrate 13 is in equal. Note that the components Q _a and Q _{b in the} direction along the inclined surface 31 of the external forces F _a and F _b do not contribute at all to the force that presses the inclined surface 31 of the holding member 15, and thus the description thereof will be omitted.

The operation of the light source device 1 having the above configuration will be described below with reference to a partially enlarged view of the light source device 1 shown in FIG.
As shown in FIG. 2, when an external force P _b is applied to the inclined surface 31 of the holding member 15 by the pressing member 16 _b , the holding member 15 has a component force P _{b1 in the} direction along the surface of the substrate 13 and the substrate 13. component force P _b2 in the direction perpendicular to the surface acts. Here, since the external force that balances the component forces in the direction along the surface of the substrate 13 is applied to the holding member 15, the component force P _{b1 in the} direction along the surface of the substrate 13 is canceled out. On the other hand, the component force P _b2 in the direction perpendicular to the surface of the substrate 13 is transmitted from the holding member 15 to the substrate 13, and the back surface of the substrate 13 is pressed against the radiator 14 via the heat radiation grease 25.

  As described above, according to the light source device 1 according to this embodiment, the pressing member 16 balances the component forces in the direction along the surface of the substrate 13 with respect to the two or more inclined surfaces 31 of the holding member 15. When an external force is applied to the substrate 13, a component force is generated in a direction perpendicular to the surface of the substrate 13 with respect to the holding member 15 and the substrate 13 fixed to the holding member 15, and the contact pressure to the radiator 14 on the back surface of the substrate 13 increases. Be made. Thereby, the contact thermal resistance between the board | substrate 13 and the heat radiator 14 can be reduced, without applying a load directly to the light guide member 12, and without affecting the optical characteristic of the light guide member 12, It becomes possible to improve the heat dissipation efficiency.

As a first modification of the present embodiment, as shown in FIG. 3, the position of the intersection of the normal line at the point of action of the external force applied by the pressing member 16 and the surface of the substrate 13 is the holding member 15 and the substrate. 13 may be within the range of the contact surface.
By doing so, the deflection of the holding member 15 can be prevented, and the positional relationship between the light guide member 12 held by the holding member 15 and the light source 11 can be prevented from changing. Become.

As a second modification of the present embodiment, as shown in FIG. 4B, the angle formed by the inclined surface 31 of the holding member 15 and the surface of the substrate 13 may be 45 ° or less. . As a comparative example, FIG. 4A shows a case where the angle formed by the inclined surface 31 of the holding member 15 and the surface of the substrate 13 is larger than 45 °.
According to the light source device according to this modification shown in FIG. 4B, the component force P _b2 acting in the direction orthogonal to the surface of the substrate 13 is increased as compared with the case shown in FIG. Therefore, the load applied to the holding member 15 by the pressing member 16 can be reduced. Thereby, the bending of the holding member 15 can be prevented.

[Second Embodiment]
Next, a second embodiment of the present invention will be described below with reference to FIGS.
The light source device according to the present embodiment is different from the first embodiment in that a radiator is formed in a substantially cylindrical shape, and a plurality of light sources, light guide members, and holding members are arranged inside the radiator. It is. Hereinafter, regarding the light source device of the present embodiment, description of points that are the same as those of the first embodiment will be omitted, and differences will be mainly described.

FIG. 5 is a top view illustrating the configuration of the light source device 2 according to the present embodiment, and FIG. 6 is a schematic diagram illustrating a longitudinal sectional view of the radiator in the axial direction.
The light source device 2 according to this embodiment includes a radiator 14 formed in a substantially cylindrical shape, a plurality of light source units 5 arranged in contact with the inner surface of the radiator 14, and illumination light emitted from the light source unit 5. An illumination rod 32 that guides light, a reflection member 34 that reflects illumination light guided to the illumination rod 32 in the axial direction of the radiator 14, a motor 35 that rotationally drives the illumination rod 32 and the reflection member 34, and an annular shape And a pressing member 36 formed on the surface.

  The light source unit 5 includes a light source 11, a light guide member 12, a holding member 15, and a substrate 13, and a plurality of light source units 5 are arranged at intervals in the circumferential direction inside the radiator 14. That is, the light source unit 5 is arranged in an annular shape around the axis L of the radiator 14. The light source unit 5 is arranged so that the direction of the center O of the radiator 14 is the optical axis, and emits high-intensity illumination light instantaneously by sequentially turning on the pulse. Yes.

  The reflecting member 34 is, for example, a triangular prism, and reflects the illumination light emitted from the light source unit 5 and guided by the illumination rod 32 in the extending direction of the axis L.

  The motor 35 rotates the illumination rod 32 and the reflecting member 34 within the rod folder 33. Further, the motor 35 is configured to cause the illumination light emitted from the light source unit 5 to enter the illumination rod 32 and the reflecting member 34 by synchronizing the pulse lighting timing of the light source unit 5 and the phase of the motor 35. Yes. By doing in this way, the high-intensity illumination light emitted by each light source unit 5 being pulsed is emitted continuously in the axial direction of the radiator 14.

  The pressing member 36 is a member formed in an annular shape so that a part of the pressing member 36 enters the inner surface side of the radiator 14. 14 is fixed. Further, an elastic body 37 such as rubber is provided on the contact surface between the pressing member 36 and the holding member 15 in order to absorb the tolerance of each member.

The operation of the light source device 2 having the above configuration will be described below using a partially enlarged view of the light source device 2 shown in FIG.
As shown in FIG. 7, when fixing the pressing member 36a and the pressing member 36b at a predetermined position of the radiator 14 by the screws 41, the external force _{P a} and the external force _{P b,} respectively, it is applied to the inclined surface 31 of the holding member 15. That is, the component force P _a1 and the component force P _b1 act on the holding member 15 in a direction along the surface of the substrate 13, and the component force P _a2 and the component force P _b2 act on the holding member 15 in a direction orthogonal to the surface of the substrate 13. Here, the component force P _a1 and the component force P _b1 in the direction along the surface of the substrate 13 are equal in magnitude and opposite in direction, and thus cancel each other. On the other hand, with respect to the component force P _a2 and the component force P _b2 in the direction orthogonal to the surface of the substrate 13, the resultant force is transmitted from the holding member 15 to the substrate 13, and the outer surface of the substrate 13 is radiated through the heat radiation grease 25. 14 to be pressed.

As described above, according to the light source device 2 according to the present embodiment, the pressing member 36 sandwiches a plurality of holding members 15 arranged on the inner surface side of the radiator 14 from the outside in the axial direction of the radiator 14, With the external force applied to the inclined surface 31 of the holding member 15, each substrate 13 to which the plurality of holding members 15 are fixed can be fixed so as to be pressed against the radiator 14. Thereby, the pressing member 36 can be shared with the plurality of holding members 15, the number of parts can be reduced, and the attaching operation of the pressing member 36 can be facilitated. Moreover, the external force applied to the inclined surface 31 of each holding member 15 can be made substantially uniform, and the force pressing the back surface of the substrate 13 against the radiator 14 can be made substantially uniform. As a result, the heat dissipation efficiency of each light source 11 can be made equal, and the amount of illumination light emitted from each light source 11 can be made uniform.
Here, the illumination light emitted from each light source 11 is guided by the light guide member 12 disposed toward the center of the radiator 14 formed in a substantially cylindrical shape, and the axis of the radiator 14 by the reflecting member 34. Reflected in the direction. Therefore, it is possible to continuously irradiate stable illumination light by making the amount of illumination light emitted from each light source 11 uniform.

  As a modification of the present embodiment, as shown in FIG. 8, the pressing member 46 a is fixed to the radiator 14, and the pressing member 46 b is held between the pressing member 46 b and the holding member 15. 15, a fastening portion 45 (fastening means) that moves the pressing member 46 b in the axial direction of the radiator 14 by rotating around the axis of the radiator 14 is provided, and between the pressing member 46 b and the holding member 15. The annular sliding member 42 that slides the pressing member 15 may be sandwiched.

  By doing so, the pressing member 46 b can be easily moved in the axial direction of the radiator 14 by rotating the pressing member 46 b around the axis of the radiator 14 with respect to the holding member 15 by the fastening portion 45. it can. As the specific fastening portion 45, for example, the heat radiator 14 may be subjected to female screw processing, and the male screw processing corresponding to the female screw may be performed on the outer peripheral portion of the pressing member 46b.

  Further, since the annular sliding member 42 that slides the pressing member 46 b is sandwiched between the pressing member 46 b and the holding member 15, the rotational torque when the pressing member 46 b is rotated causes the holding member 15 to rotate. Can be prevented. For example, the sliding member 42 may be an annular member such as a washer. Further, by providing the sliding member 42 with an elastic body 43 such as rubber, it becomes possible to absorb the dimensional tolerances of the pressing member 46b, the holding member 15 and the like. The pressing member 46a may also be provided with a fastening portion similarly to the pressing member 46b so as to be movable in the axial direction of the radiator 14.

Next, an example in which the light source device 2 according to the present embodiment is applied to an endoscope apparatus will be described below.
As shown in FIG. 9, the endoscope apparatus 10 according to this application example emits illumination light to a scope unit 50 to be inserted into a human body and the scope unit 50, and performs image processing on an image acquired by the scope unit 50. And a display monitor 70 for displaying an image subjected to image processing by the main body unit 60.

The scope unit 50 includes an imaging lens 51, an imaging element 52 such as a CCD, and a light guide 53 that guides illumination light to be irradiated onto the observation site.
The main body unit 60 includes the light source device 2 described above, a rotation drive control unit 61 that controls the rotation drive of the motor 35 provided in the light source device 2, and a light source control that controls the amount of illumination light emitted to the scope unit 50. Unit 62, image sensor control unit 63 that controls image sensor 52, video signal processing unit 64 that performs processing such as color conversion on the video signal, and processing such as format conversion on the video signal for display on display monitor 70. And a display signal processing unit 65 for performing the above.

The operation of the endoscope apparatus 10 having the above configuration will be described below.
First, the user sets a color mode or the like via an input unit (not shown), and the light source control unit 62 determines the amount of illumination light emitted to the scope unit 50. Further, the rotation drive control unit 61 controls the rotation of the motor 35 so that the pulse lighting timing of the light source unit 5 provided in the light source device 2 and the phase of the motor 35 are synchronized.

  Illumination light is irradiated by the light source device 2 controlled in this way, and the illumination light is supplied to the distal end portion of the scope unit 50 via the light guide 53 and irradiated to the observation site. Then, the image of the observation site irradiated with the illumination light is acquired by the imaging lens 51 and the imaging element 52 based on a command from the imaging element control unit 63 and is output to the video signal processing unit 64 as a video signal.

  The acquired video signal is subjected to processing such as color conversion by the video signal processing unit 64 and then subjected to processing such as format conversion necessary for display on the display monitor 70 by the display signal processing unit 65. And displayed on the display monitor 70.

  According to the endoscope apparatus 10 as described above, the light source device 2 provided inside the main body device unit 60 stabilizes the illumination light irradiated to the observation unit inside the human body via the scope unit 50 with high luminance. Thus, the image quality of the video signal acquired by the image sensor 52 can be improved.

As mentioned above, although each embodiment of the present invention has been described in detail with reference to the drawings, the specific configuration is not limited to this embodiment, and includes design changes and the like without departing from the gist of the present invention. .
For example, in the application example described above, the example in which the light source device according to the present invention is applied to an endoscope apparatus has been described, but it may be applied to an illumination device such as a projector.

1 is a schematic diagram illustrating a configuration of a light source device according to a first embodiment of the present invention. It is the elements on larger scale of the light source device of FIG. It is the elements on larger scale of the light source device which concerns on the 1st modification of FIG. It is the elements on larger scale of the light source device which concerns on the 2nd modification of FIG. 1, (a) is a case where the angle which a board | substrate and a slope make is larger than 45 degrees, (b) is a case of 45 degrees or less. It is a top view explaining the light source device which concerns on the 2nd Embodiment of this invention. It is a schematic diagram of the longitudinal cross-section explaining the structure of the light source device of FIG. It is the elements on larger scale of the light source device of FIG. It is a schematic diagram explaining the structure of the longitudinal cross-section of the light source device which concerns on the modification of FIG. FIG. 6 is a functional block diagram of an endoscope apparatus to which the light source device of FIG. 5 is applied.

Explanation of symbols

1, 2, 3 Light source device 10 Endoscope device 11 Light source 12 Light guide member 13 Substrate 14 Radiator 15 Holding member 16, 16a, 16b, 36, 36a, 36b, 46, 46a, 46b Press member 31 Inclined surface 34 Reflection Member 42 Sliding member 45 Fastening part L Axis O center

Claims (6)

A substrate,
A light source attached to the surface of the substrate and emitting illumination light;
A light guide member that guides illumination light emitted from the light source;
A radiator that is disposed in contact with the back surface of the substrate and absorbs and dissipates heat of the substrate;
A holding member that is fixed to the surface side of the substrate and has two or more inclined surfaces that gradually approach each other as the distance from the surface of the substrate increases, and holds the light guide member at a position facing the light source;
A light source device comprising: a pressing member that applies an external force such that a component force in a direction along the surface of the substrate is balanced against the inclined surface of the holding member.   The position of the intersection of the normal line of the said inclined surface and the surface of the said board | substrate in the action point of the external force applied by the said pressing member becomes in the range of the contact surface of the said holding member and the said board | substrate. Light source device.   The light source device according to claim 1, wherein an angle formed between the inclined surface and the surface of the substrate is 45 ° or less. The radiator is formed in a substantially cylindrical shape,
A plurality of the light source, the light guide member, the holding member, and the substrate are disposed on the inner surface side of the radiator, with an optical axis disposed toward the center and spaced in the circumferential direction.
A reflection member that reflects the illumination light emitted from the light source and guided by the light guide member in the axial direction of the radiator;
4. The pressure member according to claim 1, wherein the pressing member is formed in an annular shape and is fixed to the inner surface side of the radiator so as to sandwich the plurality of holding members from the outside in the axial direction of the radiator. The light source device according to 1. Fastening means for moving the pressing member in the axial direction of the radiator by rotating the pressing member around the radiator with respect to the holding member is provided,
The light source device according to claim 4, wherein an annular sliding member that slides the pressing member is sandwiched between the pressing member and the holding member. An endoscope apparatus comprising the light source device according to any one of claims 1 to 5,
An image pickup device for obtaining an image of an observation site irradiated with illumination light guided by the light guide member;
A video signal processing unit that performs at least color conversion processing on the video signal acquired by the imaging device;
An endoscope apparatus comprising: a display monitor that displays an image subjected to image processing by the video signal processing unit.

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