JPH07153308A - Lighting device for enlarging image pick-up device - Google Patents

Abstract

PURPOSE:To obtain a lighting device for an enlarging image pick-up device which has simple structure and can arbitrarily adjust the balance of light quantity of fall light and side light. CONSTITUTION:This is lighting device for an enlarging image pick-up device in which a lighting head 2 is mounted on the tip of a cylinder body 1 for housing a lens unit for an image pick-up element and image formation, ring-like light flux is emitted into the lighting head 2 from the tip 14 of the cylinder body 1 by an optical fiber 4, and a part or the whole of the emitted light is reflected by the reflecting surface 22a provided within a lighting head 2 to irradiate an object. A ring-like lens device 5 is provided in the vicinity of the emitting end of the optical fiber 4. In the lens device 5, the diameter of the ring is changed, thereby changing the boundary plane through which light passes. Thereby, the direction of refraction of light L is changed, so that the balance of light quantity of side light L1 and fall light L2 may be controlled.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a magnifying image pickup apparatus for picking up an image of various objects such as the surface of an object or the skin of a human body and displaying the magnified image on a monitor. The lighting device of the present invention.

[0002]

2. Description of the Related Art In a magnified image pickup apparatus of this type, it is necessary to perform appropriate illumination according to the unevenness of the surface of an object. Therefore, for example, an enlarged image pickup apparatus has been proposed that includes an illumination device that can illuminate an object with irradiation light not only from one direction but also by changing the irradiation angle (for example, Japanese Examined Patent Publication No. 3-9445). See the bulletin). An example of this type of lighting device is shown in FIG.

In FIG. 7, a second reflector ring 110 is concentrically arranged outside the first reflector ring 100. A first reflecting surface 101 is formed on the outer peripheral surface of the first reflector ring 100. A second reflecting surface 111 is formed on the inner peripheral surface of the second reflector ring 110 so as to face the first reflecting surface 101. Both reflector rings 10 above
0 and 110 are connected to a differential device (not shown) that moves them at a predetermined speed ratio. The first reflecting surface 1
01 is irradiated with a ring-shaped light beam (light flux) La from a large number of optical fibers 4.

The operation of the above configuration will be described. A ring-shaped light beam La emitted from the emission end of each optical fiber 4.
Are reflected radially outward by the first reflecting surface 101 to be collimated light and enter the second reflecting surface 111. Second reflective surface 1
The light incident on 11 is reflected toward a converging point, that is, an object. The angle of incidence on this condensing point changes depending on the relative positions of the two reflector rings 100 and 110 and the position with respect to the object, as shown in this figure.

[0005]

By the way, in this type of magnifying image pickup apparatus, in order to obtain a clear image of an object having various surface shapes, an incident light projected from the front of the object surface, It is necessary to appropriately set the balance (intensity ratio) with the side radiant light projected from the side close to the object surface.

Therefore, the above-mentioned conventional illuminating device which merely changes the incident angle cannot adjust the balance between the incident light and the side incident light, so that a clear image corresponding to the surface shape of the object cannot be obtained.

Moreover, the above-mentioned prior art requires a differential device for moving both reflector rings 100, 110 at a predetermined speed ratio. Therefore, the size of the entire apparatus is increased and the cost is increased.

The present invention has been made in view of the conventional problems described above, and provides a compact and inexpensive lighting device capable of adjusting the light quantity balance between incident light and side light in an enlarged image pickup device. With the goal.

[0009]

SUMMARY OF THE INVENTION According to the present invention, an illumination head is attached to a front end of a cylindrical body having a camera section accommodating an image pickup element and a lens section accommodating a lens unit for image formation, and a light guide. It is applied to an illuminating device for a magnifying image pickup device which causes a ring-shaped light beam to be emitted from the tip of the cylindrical body into the illumination head by means, and guides the emitted light into the illumination head to illuminate an object.

According to the first aspect of the present invention, the light guide means is arranged or formed in a ring shape so as to face the vicinity of the exit end of the light guide means, collects light, and changes the boundary surface through which the light passes. By doing so, a lens device for illumination that changes the direction in which light is refracted is provided.

On the other hand, the invention of claim 2 is a lens device which is arranged or formed in a ring shape so as to face the vicinity of the emission end of the light guide means, collects light, and has a variable ring diameter. A support device for movably supporting the lens device in the radial direction of the ring and a scaling device for changing the diameter of the ring of the lens device are provided.

It is preferable that the supporting device is formed of a transparent member that transmits light, and supports the lens device at a part of the ring in the circumferential direction. Further, it is preferable that each of the lens devices is composed of a plurality of arcuate lens bodies. Further, the expansion / contraction device includes an actuating member which penetrates the illumination head and pushes the lens body inward in the radial direction to move the lens body, and a spring member which moves the lens body outward in the radial direction. Is preferred.

[0013]

The principle of the present invention will be described with reference to FIG. When the light L from the light guide means 4 passes through the lens device 5, the light L is refracted at the boundary surface 50 a of the lens. Therefore, as shown in FIG. 4A, when the tangent line T in contact with the boundary surface 50a of the lens and the principal ray axis S of the light beam La are set to be orthogonal to each other, the light L emitted from the light guide means 4 is emitted. Most of the light is condensed in the lens while being slightly refracted, goes straight, is reflected by a reflection surface provided in the illumination head, and is irradiated as side-emitted light to the object. On the other hand, as shown in FIG. 4C, the tangent line T contacting the boundary surface 50a of the lens is the light beam La.
When it is set to be oblique with respect to the principal ray axis S of, most of the emitted light L from the light guide means 4 is largely refracted and is radiated to the object as incident light. Therefore, FIG.
By setting the boundary surface 50a of the lens at an intermediate position between the above two states as shown in FIG.
By changing 0a, the light amount balance between the incident light and the side incident light can be arbitrarily set.

According to the second aspect of the present invention, since the diameter of the ring of the lens device is changed, the boundary surface through which the light passes changes. With such a configuration, only by providing a supporting device that movably supports the lens device in the radial direction of the ring and a scaling device that changes the diameter of the ring of the lens device,
The boundary surface can be changed. Therefore, the present invention can be easily realized.

If the supporting device is formed of a transparent member and a part of the lens device in the circumferential direction is supported by the supporting device, the proportion of light absorbed by the supporting device is reduced, so that the efficiency of illumination is improved. improves.

On the other hand, if a lens device is constructed by arranging a plurality of arc-shaped lens bodies divided into a ring shape, the diameter of the ring of the lens device can be easily changed by moving each lens body. Therefore, the present invention can be realized more easily.

[0017]

Embodiments of the present invention will be described below with reference to the drawings. 1 to 4 show a first embodiment of the present invention. Figure 1
In the above, the magnified imaging device has a tubular body 1 including a camera unit 1 a and a lens unit 1 b, an illumination head 2 attached to the tip of the lens unit 1 b, and an operation member 3. An image pickup element 12 and a lens unit 13 for image formation are provided inside the hollow portion 11 of the camera portion 1a and the lens portion 1b of the cylindrical body 1, respectively. This magnified image pickup device irradiates an object in front of the illumination head 2 with light by an illumination device described below, forms an image of the object on the image pickup element 12 by the lens unit 13, and monitors it (not shown). ), Etc., to display a magnified image on a display device. In addition,
The cylindrical body 1 may be divided into a camera portion 1a and a lens portion 1b, or may be integrally formed.

At the base end of the cylindrical body 1, an optical fiber (light guiding means) 4 in which a large number of strands are bundled is inserted. As shown in FIG. 2A, the optical fiber 4 is fixed by a fixing ring 15 at the tip of the tubular body 1 and is arranged in a ring shape. Therefore, light from a light source (not shown) is emitted. And a ring-shaped luminous flux (light ray bundle) is emitted from the tip 14 of the cylindrical body 1 into the illumination head 2. Although only a few optical fibers 4 are shown in FIG. 2B, they are actually arranged in a ring shape over the entire circumference.

In FIG. 2A, the illumination head 2
Includes an inner cylinder 21 having a first reflecting surface 21a and an outer cylinder 22 having a second reflecting surface 22a. These reflection surfaces 21a and 22a reflect a part or all of the light emitted from the tip of the optical fiber 4, and irradiate the surface (not shown) of the object from the illumination hole 22b of the outer cylinder 22. The second reflection surface 22a has a concave end such as a paraboloid of revolution or a hyperbolic surface.

A lens device 5 for illumination is arranged in a ring shape near the emitting end of the optical fiber 4 as shown in FIG. 2B. The lens device 5 is composed of, for example, a lens body 50 divided into four, and the diameter of the ring is variable. As shown in FIG. 2A, the lens body 50 has a circular cross section, for example,
By collecting the light from the optical fiber 4, the efficiency of illumination is improved.

The lens device 5 is supported by a support device 6 described below so as to be movable in the radial direction R of the ring. The supporting device 6 includes four acrylic plates 61.
And four acrylic pieces 62. The acrylic plate 61 is pressed against the tip of the tubular body 1 by the inner cylinder 21 and the outer cylinder 22.
Is inserted between the front end surface of the lens and the lens device 5. on the other hand,
Each of the acrylic pieces 62 is integrally formed with a tapered cylindrical light guide member 63 attached to the outer periphery of the inner cylinder 21,
It is arranged so as to face each of the acrylic plates 61. As shown in FIG. 2B, the acrylic piece 62 and the acrylic plate 61 support the end (part) of the arc-shaped lens body 50 and support the lens body 50 so as to be movable in the radial direction. There is.
The acrylic plate 61 engages with the inner cylinder 21 in the circumferential direction and does not rotate in the circumferential direction. The light guide member 63 efficiently guides the incident light to the illumination hole 22b.

The outer cylinder 22 shown in FIG. 1 is fixed to the cylinder 1 by being screwed into the tip of the cylinder 1, and the inner cylinder 21 is fixed to the tip of the cylinder 1 via the light guide member 63. It is fixed. The union nut-shaped operation member 3 is screwed onto the outer circumference of the outer cylinder 22.

In the lens device 5, the diameter of the ring, that is, the distance from the lens body 50 to the optical axis C is changed by the operation of the expansion / contraction device 7 which will be described later in detail, as shown in FIGS. Changes to. The expansion / contraction device 7 changes the diameter of the ring of the lens device 5 to change the boundary surface 50a of the lens body 50 through which the light L of FIG. 4 passes, thereby changing the refraction direction of the light L. Thereby, as will be described later, the light amount balance between the side incident light and the incident light is arbitrarily set.

In FIG. 2, the expansion / contraction device 7 includes a driven pin (operating member) 71 screwed into the lens body 50.
And a cam surface 72 formed of a tapered circumferential surface formed on the inner circumference of the operation member 3, and a diameter expansion spring 73 mounted in a recess of the inner cylinder 21. The driven pin 71
Penetrates the sliding hole 22c formed in the outer cylinder 22 in the radial direction, and the hemispherical portion 71a comes into contact with the cam surface 72,
By screwing the operation member 3 into the distal end side A, the operation member 3 is moved inward in the radial direction R together with the lens body 50, and the ring diameter of the lens device 5 is reduced. On the other hand, by loosening the operating member 3 to the rear side B, the expanding spring 73 moves the lens body 50 together with the driven pin 71 outward in the radial direction R to increase the ring diameter of the lens device 5.

The lens body 50, the light guide member 63 and the driven pin 71 are made of acrylic. Also,
The both reflecting surfaces 21a and 22a are formed of metal surfaces that are processed so as to appropriately reflect light.

Next, a method of using the magnified image pickup apparatus will be described with reference to FIG. In FIG. 3, in order to facilitate understanding of the invention, the illustration of the light guide member 63 (FIG. 2) and the description of the action of the light guide member 63 are omitted. First, as shown in FIG. 3A, the lens body 5 is moved to the side emission position P1 where the normal direction of the lens body 50 matches the axial direction of the optical fiber 4.
Set the 0 position. In this state, most of the light L from the optical fiber 4 travels straight, while being condensed by the lens body 50, and then is reflected by the concave surface of the second reflection surface 22a, so that the surface of the object (not shown) may be reflected. Illuminate from the side. Therefore, since the light reflected on the surface of the object does not go in the optical axis C direction of the lens unit 13 (FIG. 1), even an object having an extremely smooth surface can prevent halation and the like. , Measurement becomes possible.

On the other hand, when an image of an object having a large surface irregularity is taken, the operating member 3 is screwed in the direction of arrow A as shown in FIG. The light L from the optical fiber 4 is moved in the direction R inward.
Is set to the epi-illumination position P3 where the incident angle is large. In this state, the light L diverging from the optical fiber 4 is largely refracted while being condensed by the lens body 50, and then illuminates the object from the front. Therefore, it is possible to irradiate the light L even on the concave portion of the object having the large unevenness on the surface.

Further, for an object whose surface unevenness is not so large or uneven, or the like, the above-mentioned incident light position P3.
3 which is an intermediate position between the side emission position P1 of FIG.
The position of the lens body 50 is set to the intermediate position P2 in (b). In this state, a part of the light L diverging from the optical fiber 4 travels substantially straight as shown by an arrow L1 while being condensed by the lens body 50, and then reflected by the concave surface of the second reflecting surface 22a, which is not shown. Illuminate the surface of the object from the side. on the other hand,
A part of the light L diverging from the optical fiber 4 is generated by the lens body 50.
The object is illuminated from the front as shown by an arrow L2 while being condensed by. The light amount balance between the incident light L2 from the front and the side incident light L1 from the side is increased by moving the lens body 50 outward in the radial direction R, while the light amount of the side incident light L1 is increased. By moving 50 inward in the radial direction R, the amount of incident light L2 increases. Therefore, the operator operates the operation member 3 while looking at the image displayed on the monitor to arbitrarily adjust the balance between the incident light L2 and the side incident light L1 to obtain the optimum condition according to the surface state of the object. Images can be projected with a good balance of light intensity.

Further, since the light quantity balance can be adjusted only by moving the lens body 50 in the radial direction R, that is, the two reflector rings 10 are different from the conventional example of FIG.
Since it is not necessary to move 0 and 110 by a differential device at a predetermined speed ratio, the light amount balance can be adjusted with a simple device such as the expansion / contraction device 7 in FIG.

Further, as shown in FIG. 2B, in this first embodiment, the supporting device 6 supports only both ends of the lens body 50, and the supporting device 6 is not provided over the entire circumference. The acrylic plate 61 and the acrylic piece 6 of FIG.
The amount of light L absorbed by 2 can be reduced. Therefore, the object L can be efficiently irradiated with the light L.

By the way, in the first embodiment, the lens device 5 is constituted by the four lens bodies 50, but the lens device 5 may be divided into two or more. Also, the lens body 5
0 is only required to reduce the spread angle of the light beam, that is, to condense the light L, and therefore its cross-sectional shape does not need to be circular.

In the above embodiment, the expanding spring 73 is composed of the compression coil spring, but the expanding spring 73 may be composed of a leaf spring or another spring member. Further, in the above-described embodiment, the lens body 50 is moved outward in the radial direction R by the expanding spring 73, but by providing the two cam surfaces on the operating member 3 without providing the expanding spring 73, The driven pin 71 may be moved inward and outward in the radial direction R.

Further, it is not necessary to screw the driven pin 71 into the lens body 50 to fix it, and the driven pin 71 is fixed to the lens body 5.
You may adhere to 0. Further, the driven pin 71 does not need to be made of a transparent member.

In the first embodiment, the plurality of lens bodies 50 are moved simultaneously by the expansion / contraction device 7, but the position of the driven pin 71 may be adjusted individually without providing the operating member 3. . In this case, by changing the distance from each lens body 50 to the optical axis C between the lens bodies 50 in FIG. 2B, the amount of side-light and incident-light can be changed for each lens body 50. You can

In the above embodiment, the lens body 50 is moved only in the radial direction R, but the lens body 50 is moved in the radial direction R.
It may be moved in the axial direction of the optical axis C while being moved to.

The shape of the lens body 50 does not have to be arcuate, and the lens device 5 may be composed of a large number of spherical lens bodies 50 as in the modification of FIG. 5A. Further, the supporting device 6 such as the acrylic plate 61 may be a complete ring as in this modification.

FIG. 5B shows another modification of the lens device 5. In this figure, the lens device 5 is made of a stretchable material such as transparent rubber, and has a complete annular shape. In this case, the lens device 5 can be expanded from the inside to the whole, and the diameter of the ring can be changed to adjust the light amount balance as in the first embodiment. The lens device 5 may be cut along the chain double-dashed line E.

In addition, in the above-described embodiment and modification, the diameter of the ring of the lens device 5 is changed to change the state shown in FIGS.
Although the boundary surface 50a through which the light L passes is changed as shown in (c), the method is not necessarily limited to this method. For example, as in the second embodiment described below, the lens device 5 can be used.
By changing the cross-sectional shape of the lens part of
You may change the shape of the boundary surface which passes.

FIG. 6 shows a second embodiment. In FIG. 6A, the lens device 5 has a circular cross section, and is entirely a (continuous) annular ring. The lens device 5 is made of a transparent rubber-like member, and the cross-sectional shape and the diameter of the ring change when an external force is applied. The illumination head 2 also serves as an operating member, and a compression plate 8 that compresses the lens device 5 is engaged with the illumination head 2. The compression plate 8 is
As shown in FIG. 6B, it is formed in an annular shape and has a taper-shaped expanded portion 81 that expands the diameter of the lens device 5 when the lens device 5 is compressed. Therefore, by screwing the illumination head 2 into the tube body 1, the lens device 5 is compressed to have a flat cross section as shown in FIG. The diameter of the device 5 is slightly increased.

In the second embodiment, unlike the above-described first embodiment, it is not possible to set the case where only the incident light is used, but the light quantity balance can be set to some extent, and thus is included in the present invention. .

[0041]

As described above, according to the present invention,
By changing the boundary surface of the lens through which the ring-shaped light flux passes, the direction in which the light is refracted is changed, so that the light can be efficiently collected and the side that is reflected by the reflecting surface in the illumination head. It is possible to change the balance between the incident light and the incident light emitted from the front of the object to any ratio. Therefore, it is possible to perform appropriate illumination according to the surface shape of the object. Further, the structure is simplified because only the boundary surface through which light passes is changed.

According to the second aspect of the invention, since the boundary surface through which the light passes is changed by changing the diameter of the ring of the lens device, the support for movably supporting the lens device in the radial direction of the ring. A simple structure may be provided only by providing the device and the expansion / contraction device for changing the diameter of the ring of the lens device. Therefore, the present invention can be easily realized.

Further, according to the invention of claim 3, since a part of the lens device in the circumferential direction is supported by the supporting device, the proportion of light absorbed by the supporting device is reduced.
Lighting efficiency is improved.

On the other hand, according to the invention of claim 4, since the lens device is constructed by arranging a plurality of arcuate lens bodies divided into a ring shape, each lens body has a ring diameter. By moving in the direction, the diameter of the ring of the lens device can be changed very easily. Therefore, the implementation of the present invention becomes easier.

Further, according to the invention of claim 5, since the actuating member for pushing and moving the lens body inward in the radial direction and the spring member for moving the lens body outward in the radial direction are provided, the ring is provided. The diameter of the ring of the device can be easily changed.

[Brief description of drawings]

FIG. 1 is a schematic external view of a magnified image pickup apparatus according to a first embodiment of the present invention.

2A is a vertical cross-sectional view showing the illumination head and the like taken along line IIa-IIa in FIG. 2B, and FIG. 2B is IIb- in FIG.
It is a cross-sectional view taken along line IIb.

3A to 3C are cross-sectional views showing changes in illumination state.

4A to 4C are principle diagrams showing changes in a boundary surface through which light passes.

5A is a schematic plan view showing a modified example of the lens device, which is a main part of the first embodiment, and FIG. 5B is a plan view showing another modified example.

FIG. 6 is a vertical cross-sectional view of a main part showing a second embodiment of the present invention.

FIG. 7 is a vertical cross-sectional view showing an optical system of a conventional lighting device.

[Explanation of symbols]

 1: Cylindrical body 1a: Camera part 1b: Lens part 12: Imaging element 13: Lens unit 14: Tip 2: Illumination head 21a: (First) reflective surface 22a: (Second) reflective surface 4: Optical fiber (light guide) Means) 5: Lens device 50: Lens body 50a: Boundary surface 6: Support device 7: Expansion / contraction device 71: Driven pin (operating member) 73: Expansion / contraction spring (spring member) L: Light R: System direction

Claims (5)

[Claims] 1. An illumination head is attached to a front end of a cylindrical body having a camera section accommodating an image pickup element and a lens section accommodating a lens unit for image formation, and is guided from the distal end of the cylindrical body by a light guiding means. An illumination device for a magnifying image pickup device, which emits a ring-shaped light beam into the illumination head, guides the emitted light into the illumination head to irradiate an object, and in the vicinity of an emission end of the light guide means. Enlarged imaging provided with a lens device for illumination that is arranged or formed in a ring shape to face the light source, collects light, and changes the direction in which light is refracted by changing the boundary surface through which light passes. Lighting equipment for equipment. 2. An illumination head is attached to a front end of a cylindrical body having a camera section accommodating an image pickup device and a lens section accommodating a lens unit for image formation, and is guided from the distal end of the cylindrical body by a light guiding means. An illumination device for a magnifying image pickup device, which emits a ring-shaped light beam into the illumination head, guides the emitted light into the illumination head to irradiate an object, and in the vicinity of an emission end of the light guide means. A lens device that is arranged or formed in a ring shape to face the lens, collects light, and has a variable diameter of the ring; a support device that supports the lens device so as to be movable in the radial direction of the ring; An illuminating device for a magnifying image pickup device, comprising: a magnifying device for changing a diameter of a ring of the device. 3. The support device according to claim 2, wherein the supporting device is formed of a transparent member that transmits light, and
An illuminating device for a magnifying imaging device, which supports the lens device in a part of a ring in a circumferential direction. 4. The illumination device according to claim 2, wherein the lens device is composed of a plurality of arcuate lens bodies divided into a plurality of parts. 5. The expansion / contraction device according to claim 4, wherein the expansion / contraction device moves the lens body radially outward, and an actuating member which penetrates the illumination head and pushes the lens body radially inward. An illumination device for a magnifying image pickup device, comprising: