Imaging unit

Abstract

To provide an imaging unit that easily irradiates forward of an imaging part while suppressing increase in the number of components.SOLUTION: An imaging unit 1 includes at least: an imaging part 3 including an outer frame 30 having a square shape when being viewed from the front side; a light-emitting part 4 positioned backward from the imaging part 3 and emitting light forward; and a light guide path 5 positioned on an outer peripheral side of the imaging part 3 and guiding light emitted from the light-emitting part 4 forward more than the imaging part 3. The imaging unit comprises two light-emitting parts 4, where each of the light-emitting part 4 emits light toward adjacent two sides of the square-shaped imaging part 3.SELECTED DRAWING: Figure 5

Description

[Technical Field]

[0001] The present invention relates to an imaging unit. [Background technology]

[0002] Patent document 1 discloses an endoscope that includes a camera, a plurality of LEDs (Light Emitting Diodes) arranged behind the camera, and a light guide device that is arranged on the outer periphery of the camera and guides the light emitted from the plurality of LEDs forward. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] U.S. Patent No. 7,442,167 Summary of the Invention [Problem to be solved by the invention]

[0004] In the endoscope described in Patent Document 1, increasing the number of LEDs could be considered to increase the amount of light guided forward to the camera, but this would increase the number of parts.

[0005] The present invention has been made in view of the above-mentioned circumstances, and has an object to provide an imaging unit that can easily illuminate the area in front of the imaging section while suppressing an increase in the number of parts. [Means for solving the problem]

[0006] In order to achieve the above-mentioned object, the present invention provides an imaging unit having at least an imaging section having a rectangular outer shape when viewed from the front, a light emitting section located behind the imaging section and emitting light toward the front, and a light guide path located on the outer periphery of the imaging section and guiding the light emitted from the light emitting section to a position forward of the imaging section, wherein there are two light emitting sections, and each of the light emitting sections emits light toward two adjacent sides of the rectangular imaging section. [Effects of the Invention]

[0007] According to the present invention, it is possible to provide an imaging unit that can easily illuminate the area in front of the imaging section while suppressing an increase in the number of parts. [Brief explanation of the drawings]

[0008] [Figure 1] 1 is a schematic configuration diagram of an endoscope system including an imaging unit according to a first embodiment. [Figure 2] FIG. 2 is an end view showing the tip surface of the camera head in the first embodiment. [Figure 3] FIG. 3 is a cross-sectional view taken along the line III-III in FIG. 2. [Figure 4] FIG. 2 is a side view of the imaging unit according to the first embodiment. [Figure 5] FIG. 2 is a front view of the imaging unit according to the first embodiment. [Figure 6] FIG. 2 is a cross-sectional view of the cable according to the first embodiment. [Figure 7] FIG. 10 is a front view of an imaging unit according to a second embodiment. [Figure 8] FIG. 11 is a front view of an imaging unit according to a third embodiment. [Figure 9] FIG. 13 is a side view showing a cross section of a part of an imaging unit in a fourth embodiment. [Figure 10] FIG. 10 is a cross-sectional view taken along the line AA in FIG. 9. [Figure 11]FIG. 13 is a perspective view of a molded product of a holding member and four optical fibers in a fourth embodiment. DETAILED DESCRIPTION OF THE INVENTION

[0009] [First embodiment] A first embodiment of the present invention will be described with reference to Figures 1 to 6. The embodiment described below is shown as a preferred specific example for carrying out the present invention, and although various technically preferable technical matters are specifically exemplified, the technical scope of the present invention is not limited to this specific embodiment.

[0010] 1 is a schematic diagram of an endoscope system 10 equipped with the imaging unit 1 of this embodiment. The endoscope system 10 includes an endoscope 11, an image processing device 12 that processes image information obtained by the endoscope 11, a display device 13 that displays images processed by the image processing device 12 on a screen 131, and a liquid supply device 14 that discharges a liquid for cleaning a camera lens or the like in response to operation of a foot switch 141.

[0011] The endoscope 11 includes an operation unit 111, an insertion tube 112, and a camera head 113. The operation unit 111 is a part operated by a doctor. The operation unit 111 is connected to the image processing device 12 via a communication cable 15, and is also connected to the liquid supply device 14 via a hose 16. The insertion tube 112 connects the operation unit 111 and the camera head 113. The length of the insertion tube 112 is, for example, 1 m or more and 4 m or less. The camera head 113 is inserted into the body of the subject together with a part of the insertion tube 112.

[0012] Fig. 2 is an end view showing the tip surface of the camera head 113. Fig. 3 is a cross-sectional view taken along line III-III in Fig. 2. The camera head 113 has a resin outer cylinder 113a and a cover 113b that closes the tip of the outer cylinder 113a. A liquid supply path 17 for circulating liquid supplied from the liquid supply device 14 and the imaging unit 1 are inserted inside the outer cylinder 113a and the insertion tube 112. A fitting hole 113c into which the tip of the imaging unit 1 is fitted, and a fitting hole 113d into which the tip of the liquid supply path 17 is fitted are formed in the cover 113b.

[0013] Fig. 4 is a side view of the imaging unit 1. Note that a tube 2, which will be described later, is shown in cross section in Fig. 4. Fig. 5 is a front view of the imaging unit 1.

[0014] 4, the imaging unit 1 has a tube 2, an imaging section 3, a light emitting section 4, a light guide path 5, and a cable 6. Hereinafter, the front-to-back direction of the imaging section 3 will be referred to as the "front-to-back direction X," and one side of the front-to-back direction X, which is the field of view side of the imaging section 3, will be referred to as the front, and the opposite side will be referred to as the rear. In this embodiment, the front is also the side on which the imaging section 3 is located with respect to the cable 6.

[0015] The tube 2 is formed, for example, from resin or the like into a long cylindrical shape in the front-to-rear direction X. The tube 2 has, for example, an inner diameter of 1.0 mm or more and 2.0 mm or less. The tube 2 has, for example, a wall thickness of 0.05 mm or more and 0.10 mm or less. The tip of the tube 2 is fitted into the fitting hole 113c. Furthermore, the imaging unit 3, the light emitting unit 4, the light guide path 5, and the cable 6 are inserted inside the tube 2.

[0016] The imaging unit 3 has a rectangular prism shape that is elongated in the front-to-rear direction X. As shown in FIG. 5 , the imaging unit 3 has a rectangular outer periphery 30 when viewed from the front. The rectangular shape here does not only refer to a strict rectangular shape, but also includes an approximate rectangular shape such as a rectangle with rounded corners. In this embodiment, the imaging unit 3 has a square outer periphery 30 when viewed from the front. For example, the outer periphery 30 of the imaging unit 3 when viewed from the front is a square with each side measuring 0.6 mm to 1.2 mm. The imaging unit 3 has an imaging range in the front. Hereinafter, one of the two diagonals of the square outer periphery 30 of the imaging unit 3 when viewed from the front will be referred to as the first diagonal DL1, and the other as the second diagonal DL2.

[0017] As shown in FIG. 3, the imaging unit 3 includes a rectangular cylindrical body 31 that is long in the front-to-rear direction X, a light-transmitting imaging window 32 fixed to the tip of the cylindrical body 31, an imaging element 33 fixed to the base end of the cylindrical body 31, and a plurality of lenses 34 positioned between the imaging window 32 and the imaging element 33.

[0018] The imaging element 33 can be, for example, a complementary metal oxide semiconductor (CMOS) image sensor, a charge-coupled device (CCD) image sensor, etc. The imaging element 33 has four electrodes 331 (see FIG. 5) on the rear surface.

[0019] The four electrodes 331 are arranged vertically and horizontally in a matrix. In this embodiment, the four electrodes 331 are composed of a power supply electrode for powering the imaging unit 3, an information output electrode for outputting an imaging signal converted from information on an optical image coupled to the imaging element 33, a command receiving electrode for receiving a command signal for causing the imaging unit 3 to perform a predetermined operation (e.g., an imaging operation), and a ground electrode. The four electrodes 331 are electrically connected to four electric wires of the cable 6, respectively. The imaging unit 3 converts information on the optical image formed on the imaging element 33 into an electric signal and outputs it to the image processing device 12 via the cable 6.

[0020] 4, two light-emitting units 4 are located behind the imaging unit 3. The light-emitting units 4 are located behind and near the imaging unit 3. For example, the light-emitting units 4 are located behind the imaging unit 3 and in front of the tip of an outer sheath 66 (described later) of the cable 6. Furthermore, for example, the distance between the imaging unit 3 and the light-emitting units 4 in the front-rear direction X is shorter than the length of the imaging unit 3 in the front-rear direction X.

[0021] The light-emitting unit 4 is composed of a light-emitting diode (LED) or the like that emits light in the visible light wavelength range. As shown in FIG. 5 , the light-emitting unit 4 has a rectangular shape, more specifically, an elongated rectangular shape, when viewed from the front (the viewing side of the imaging unit 3). The light-emitting surface 40 (the entire front surface of the light-emitting unit 4 in this embodiment) from which light is extracted in the light-emitting unit 4 has a rectangular shape when viewed from the front, more preferably an elongated rectangular shape. For example, the light-emitting surface 40 has a rectangular shape whose longitudinal dimension is 1.5 times or more its lateral dimension. In this embodiment, the light-emitting surface 40 has a rectangular shape. The shape of the light-emitting surface 40 may be a substantially rectangular shape, such as a rectangle with rounded corners, or any other shape, as long as it is rectangular. The light-emitting unit 4 has a longitudinal dimension of 0.4 mm to 0.6 mm and a lateral dimension of 0.2 mm to 0.4 mm, for example. The light-emitting unit 4 is disposed in a position that allows it to emit light forward.

[0022] When viewed from the front, the light-emitting unit 4 is disposed at an angle with respect to the outer casing 30 of the imaging unit 3. In this embodiment, when viewed from the front, the light-emitting unit 4 is disposed so that its longitudinal direction is parallel to the first diagonal line DL1 and perpendicular to the second diagonal line DL2. When viewed from the front, the two light-emitting units 4 are disposed at positions spaced apart from each other on opposite sides of the center position of the imaging unit 3 in the direction along the second diagonal line DL2. By displacing the light-emitting units 4 from the center position of the imaging unit 3 when viewed from the front, it becomes easier to ensure space for connecting the imaging unit 3 and the cable 6.

[0023] Each light-emitting unit 4 has a rectangular light-emitting surface 40 when viewed from the front, and is configured to emit light from this rectangular light-emitting surface 40 toward two adjacent sides of the rectangular imaging unit 3 (outer casing 30). As a result, light emitted from the light-emitting surface 40 of the light-emitting unit 4 is guided forward of the imaging unit 3 via the light guide path 5. In this embodiment, when viewed from the front, both ends of the longitudinal direction of the light-emitting surface 40 protrude from the rectangular outer casing 30 of the imaging unit 3. Hereinafter, the portion of the light-emitting surface 40 that protrudes from the rectangular outer casing 30 of the imaging unit 3 when viewed from the front is referred to as a protruding portion 41. The protruding portion 41 of the light-emitting unit 4 emits light toward the light guide path 5 adjacent to the rectangular outer casing 30 of the imaging unit 3. Note that the light-emitting unit 4 does not need to have the protruding portion 41 as long as it is configured to emit light toward the light guide path 5 adjacent to the rectangular outer casing 30 of the imaging unit 3 when viewed from the front. When viewed from the front, a pair of protruding portions 41 of one light-emitting unit 4 protrudes from two adjacent sides of the outer casing 30 of the imaging unit 3. When viewed from the front, a pair of protruding portions 41 of the other light-emitting unit 4 protrudes from two sides other than the aforementioned two sides of the outer casing 30 of the imaging unit 3. When viewed from the front, the light-emitting unit 4 is arranged so as to fit inside an imaginary circumscribing circle C of the outer casing 30 of the imaging unit 3.

[0024] The multiple light-emitting units 4 do not have to be parallel to one another. Furthermore, the light-emitting units 4 do not have to be parallel to the first diagonal line DL1 or the second diagonal line DL2 as long as they are inclined with respect to the outer periphery 30 of the imaging unit 3 when viewed from the front.

[0025] Light emitted from each of the pair of protruding portions 41 of the light-emitting unit 4 is guided forward of the imaging unit 3 via the light guide paths 5. As a result, during medical procedures using the endoscope 11, the subject to be imaged by the imaging unit 3 is illuminated with light guided forward from the light guide paths 5. The imaging unit 1 of this embodiment includes four light guide paths 5 that propagate forward the light emitted from a total of four protruding portions 41 of the two light-emitting units 4.

[0026] The light guide 5 is made of a member that transmits light emitted by the light emitting unit 4. In this embodiment, the light guide 5 is made of four optical fibers 51 that are formed linearly in the front-rear direction X and that propagate light in the front-rear direction X. Although detailed illustration is omitted, the optical fibers 51 have a core made of, for example, quartz glass formed along the front-rear direction X, and a cladding that covers the outer periphery of the core and is made of, for example, quartz glass with a lower refractive index than the core. The optical fibers 51 have an outer diameter of, for example, 0.08 mm or more and 0.20 mm or less.

[0027] The four optical fibers 51 are arranged at positions overlapping the four protruding portions 41 in the front-rear direction X, respectively. Note that the optical fibers 51 do not necessarily have to overlap the protruding portions 41 in the front-rear direction X as long as the light emitted from the protruding portions 41 can be incident thereon. For example, even if the optical fibers 51 do not overlap the protruding portions 41, the light emitted from the protruding portions 41 can propagate forward as long as the base ends of the optical fibers 51 are within the range of the directivity half-value angle of the protruding portions 41. However, from the viewpoint of allowing as much light emitted from the protruding portions 41 to be incident on the optical fibers 51 as possible, it is preferable that the optical fibers 51 be arranged at positions overlapping the protruding portions 41 in the front-rear direction X.

[0028] The four optical fibers 51 are arranged so as to respectively follow the four side surfaces of the imaging unit 3. When viewed from the front, the four optical fibers 51 are not arranged on the extensions of the first diagonal line DL1 and the second diagonal line DL2 of the outer casing 30 of the imaging unit 3. In this embodiment, when viewed from the front, the four optical fibers 51 are arranged at the center positions of the four sides that constitute the outer casing 30 of the imaging unit 3. When viewed from the front, the optical fibers 51 are arranged so as to fit inside an imaginary circumscribing circle C of the outer casing 30 of the imaging unit 3.

[0029] 4, the position of the tip of the optical fiber 51 is aligned with the position of the tip of the imaging unit 3. The position of the base end of the optical fiber 51 is located behind the imaging unit 3 and ahead of the light-emitting unit 4. In this embodiment, the position of the base end of the optical fiber 51 is located behind the center position between the imaging unit 3 and the light-emitting unit 4 in the front-rear direction X. In this way, by bringing the base end position of the optical fiber 51 closer to the light-emitting unit 4, it becomes easier to guide the light emitted from the protruding portion 41 into the optical fiber 51.

[0030] The imaging unit 3 and the two light-emitting units 4 are electrically connected to a cable 6. Fig. 6 is a cross-sectional view of the cable 6. The cable 6 is a multi-core cable including three coaxial wires 61, one drain wire 62, two covered electric wires 63, a tape member 64 that bundles the three coaxial wires 61, the one drain wire 62, and the two covered electric wires 63, a shield conductor 65 arranged on the outer periphery of the tape member 64, and an outer sheath 66 arranged on the outer periphery of the shield conductor 65.

[0031] The coaxial cable 61 includes an inner conductor 611, an inner insulator 612 that covers the outer periphery of the inner conductor 611, and an outer conductor 613 that covers the outer periphery of the inner insulator 612. The inner conductor 611 is composed of a conductor made of a solid wire or a twisted wire. The conductor is made of, for example, copper or a copper alloy. The diameter of the inner conductor 611 can be, for example, 40 AWG (American Wire Gauge) or more and 50 AWG or less. The diameter of the inner conductor 611 is selected in consideration of the size of the imaging unit 1 and the electrical characteristics required of the inner conductor 611.

[0032] The internal insulator 612 is made of electrically insulating resin formed into a cylindrical shape. The external conductor 613 is formed by spirally winding a plurality of conductive wires around the internal insulator 612. The external conductor 613 is grounded.

[0033] The drain wire 62 is made of a conductor made of a single wire or a stranded wire. The conductor is made of, for example, copper or a copper alloy. The drain wire 62 does not have an electrically insulating coating 632 and is electrically connected to the outer conductor 613 and the shield conductor 65 of each coaxial line 61, thereby providing a ground potential.

[0034] The coated electric wire 63 includes a core wire 631 and a coating 632 that covers the core wire 631. The core wire 631 is made of a conductor made of a solid wire or a twisted wire. The conductor is made of, for example, copper or a copper alloy. The diameter of the core wire 631 can be, for example, 40 AWG (American Wire Gauge) or more and 50 AWG or less. The diameter of the core wire 631 is selected in consideration of the size of the imaging unit 1 and the electrical characteristics required of the core wire 631. The coating 632 is made of electrically insulating resin formed into a cylindrical shape.

[0035] The tape member 64 is spirally wound around the three coaxial wires 61, the drain wire 62, and the two covered electric wires 63 to bundle them together. The tape member 64 is made of electrically insulating resin formed into a tape shape.

[0036] The shielding conductor 65 is formed by spirally winding a plurality of conductive wires laterally around the tape member 64. The shielding conductor 65 may be formed by a braided wire in which a plurality of conductive wires are braided together, or by a metal foil disposed on the inner peripheral surface of the outer sheath 66. The shielding conductor 65 may also be formed by longitudinally or transversely winding a conductive tape, which is a strip of resin with a conductive layer formed on one or both sides, around the four electric wires.

[0037] The outer jacket 66 is formed to cover the shield conductor 65. The outer jacket 66 is made of, for example, an electrically insulating resin formed into a cylindrical shape.

[0038] The three coaxial wires 61, one drain wire 62, and two coated electric wires 63 are exposed forward from the tape member 64, the shield conductor 65, and the outer sheath 66, and are electrically connected to the imaging unit 3 and the light emitting unit 4.

[0039] The three coaxial lines 61 are composed of a power supply coaxial line whose internal conductor 611 is connected to a power supply electrode among the electrodes 331 of the imaging unit 3 via solder S, an information transmission coaxial line whose internal conductor 611 is connected to an information output electrode among the electrodes 331 of the imaging unit 3 via solder S, and a command transmission coaxial line whose internal conductor 611 is connected to a command receiving electrode among the electrodes 331 of the imaging unit 3 via solder S. The power supply coaxial line supplies power to the imaging unit 3. The information transmission coaxial line transmits an imaging signal output from the information output electrode. The command transmission coaxial line transmits a command signal output to the command receiving electrode.

[0040] The drain wire 62 is connected to the ground electrode of the electrodes 331 of the imaging unit 3 via solder S. Of the electric wires constituting the cable 6, the electric wires electrically connected to the imaging unit 3 (i.e., the three coaxial wires 61 and the drain wire 62) pass between the two light-emitting units 4.

[0041] The core wires 631 of the two coated electric wires 63 are connected to the anodes of the two light-emitting units 4 via solder S, respectively. The core wires 631 of the coated electric wires 63 supply power to the light-emitting units 4. Furthermore, the portions of two of the outer conductors 613 of the three coaxial lines 61 that are exposed forward from the tape member 64, the shield conductor 65, and the outer sheath 66 are twisted together, and are connected to the cathodes of the two light-emitting units 4 via solder S, respectively.

[0042] The connection portions between the four electrodes 331 of the imaging unit 3 and the three coaxial lines 61 and one drain line 62 are reinforced by being covered with a sealing unit 7. The sealing unit 7 is made of, for example, an adhesive material having electrical insulation properties. The sealing unit 7 is made of, for example, an adhesive such as acrylate, or a resin such as epoxy resin. In this embodiment, the base end position of the sealing unit 7 is forward of the light-emitting unit 4. Note that in Figures 3 and 4, for convenience, only the outer shape position of the sealing unit 7 is represented by a two-dot chain line.

[0043] The fixing of the positions of the image capturing unit 3, the light emitting unit 4, and the light guide path 5 within the tube 2 is not particularly limited, and can be achieved, for example, by filling the tube 2 with a sealant such as an adhesive so as to adhere the image capturing unit 3, the light emitting unit 4, and the light guide path 5. Alternatively, the fixing of the positions of the image capturing unit 3, the light emitting unit 4, and the light guide path 5 within the tube 2 may be achieved by forming portions within the tube 2 that connect the image capturing unit 3, the light emitting unit 4, and the light guide path 5 to the tube 2.

[0044] (Functions and Effects of the First Embodiment) The imaging unit 1 of this embodiment includes an imaging unit 3 having a rectangular outer casing 30 when viewed from the front, and a light-emitting unit 4 located behind the imaging unit 3 and emitting light forward. The imaging unit 1 includes two light-emitting units 4. Each light-emitting unit 4 emits light toward two adjacent sides of the rectangular imaging unit 3. This allows more light to be guided forward from the light-emitting units 4, making it easier to illuminate the area in front of the imaging unit 3 while minimizing the number of components in the light-emitting units 4. Furthermore, minimizing the number of components in the light-emitting units 4 allows for a reduction in the number of insulated wires used to supply power to the light-emitting units 4, thereby enabling the imaging unit 1 and a device (endoscope 11 in this embodiment) equipped with the imaging unit 1 to be made smaller and thinner. In particular, in this embodiment, each light-emitting unit 4 has an elongated light-emitting surface 40 when viewed from the front, and both longitudinal ends of the light-emitting surface 40 of each light-emitting unit 4 are disposed so as to extend beyond the two adjacent sides of the rectangular imaging unit 3 when viewed from the front. This makes it easier to ensure space behind the imaging unit 3. This makes it easier to ensure space for connecting the imaging unit 3 and the cable 6, for example.

[0045] Furthermore, the light guide path 5 is made of a material that transmits the light emitted by the light emitting unit 4. Therefore, compared to a case where the light guide path 5 is made of, for example, air, it is easier to guide the light emitted by the light emitting unit 4 to the intended location. Furthermore, particularly in this embodiment, the light guide path 5 is made of optical fiber 51, which makes it even easier to guide the light emitted by the light emitting unit 4 to the intended location.

[0046] Furthermore, when viewed from the front, the light guide path 5 is arranged to fit inside an imaginary circumscribing circle C of the outer casing 30 of the imaging section 3. This makes it easy to make the imaging unit 1 smaller in size and diameter.

[0047] The imaging unit 1 is used in an endoscope 11. The imaging unit 1 of the endoscope 11 is inserted into the body and is extremely small and thin, so an increase in the number of components of the imaging unit 1 makes it difficult to manufacture the imaging unit 1. On the other hand, as described above, the imaging unit 1 of this embodiment is configured to easily illuminate the area in front of the imaging section 3 while suppressing an increase in the number of components, and is therefore suitable for use in an endoscope 11.

[0048] As described above, according to this embodiment, it is possible to provide an imaging unit that can easily illuminate the area in front of the imaging section while suppressing an increase in the number of parts.

[0049] [Second embodiment] A second embodiment of the present invention will be described with reference to Fig. 7. Fig. 7 is a front view of an imaging unit 1 in this embodiment.

[0050] In this embodiment, the light guide 5 is filled with a bundle 50 consisting of a large number of optical fibers between the imaging unit 3 and the tube 2. In FIG. 7, the filled area of ​​the optical fiber bundle 50 is shown by hatching. In this embodiment, the inner diameter of the tube 2 is equal to the diameter of an imaginary circumscribing circle of the imaging unit 3 when viewed from the front. As a result, the light guide 5 is arranged to fit inside the imaginary circumscribing circle of the outer shell 30 of the imaging unit 3 when viewed from the front.

[0051] Other configurations of this embodiment are the same as those of the first embodiment. It should be noted that, among the symbols used in the second and subsequent embodiments, the same symbols as those used in the previously described embodiments represent the same components, etc. as those in the previously described embodiments, unless otherwise specified.

[0052] (Functions and Effects of the Second Embodiment) In this embodiment, a large number of optical fiber bundles 50 are filled between the tube 2 and the imaging unit 3, so that more light emitted from the light emitting unit 4 is guided to the front of the imaging unit 3 via the light guide path 5. In addition, the second embodiment has the same functions and effects as the first embodiment.

[0053] [Third embodiment] A third embodiment of the present invention will be described with reference to Fig. 8. Fig. 8 is a front view of an imaging unit 1 in this embodiment.

[0054] This embodiment is an example in which the light guide 5 is configured with a transparent material 52 arranged between the imaging unit 3 and the tube 2. In this embodiment, the inner diameter of the tube 2 is equal to the diameter of a virtual circumscribing circle of the imaging unit 3 when viewed from the front. Transparent materials 52 having arch-shaped cross sections perpendicular to the front-rear direction X are arranged at four locations between the four side surfaces of the imaging unit 3 and the inner surface of the tube 2. The transparent materials 52 are configured, for example, with a transparent adhesive material or the like that is filled between the tube 2 and the imaging unit 3. The rest is the same as in the first embodiment.

[0055] (Functions and Effects of the Third Embodiment) This embodiment also has the same functions and effects as the first embodiment.

[0056] [Fourth embodiment] A fourth embodiment of the present invention will be described with reference to Fig. 9 to Fig. 11. Fig. 9 is a side view showing a cross section of a part of an imaging unit 1 in this embodiment. Fig. 10 is a cross section taken along line AA in Fig. 9. Fig. 11 is a perspective view of a molded product of a holding member 8 and four optical fibers 51.

[0057] This embodiment is an imaging unit 1 that has the same basic structure as the first embodiment, but further includes a holding member 8. The holding member 8 is fitted into the tube 2, and is formed with a holding hole 81 into which the imaging unit 3 is inserted and held. The outer peripheral surface of the holding member 8 is formed in a cylindrical shape that follows the inner surface of the tube 2. The holding hole 81 of the holding member 8 is formed in a quadrangular tubular shape that follows the side surface of the imaging unit 3 so that the imaging unit 3 can be inserted. The holding member 8 is formed from the distal end position to the proximal end position of the imaging unit 3 in the front-rear direction X.

[0058] In this embodiment, the holding member 8 is made of a light-blocking member that blocks light emitted by the light-emitting unit 4. Four optical fibers 51 serving as the light guide paths 5 penetrate the holding member 8 in the front-rear direction X. The holding member 8 is made of, for example, black resin in which the four optical fibers 51 are molded. The optical fibers 51 are formed from the distal end position to the proximal end position of the holding member 8 in the front-rear direction X. Note that, for example, the optical fibers 51 may be formed longer in the front-rear direction X than the holding member 8, and the proximal ends of the optical fibers 51 may be made to protrude from the holding member 8 and be closer to the light-emitting unit 4. The rest is the same as in the first embodiment.

[0059] (Functions and Effects of the Fourth Embodiment) In this embodiment, a holding member 8 is provided which is fitted into the tube 2 and has a holding hole 81 formed therein into which the imaging unit 3 is inserted and held. Therefore, the position of the imaging unit 3 relative to the tube 2 can be easily fixed.

[0060] Furthermore, the holding member 8 is made of a light-blocking member that blocks light emitted by the light-emitting unit 4, and the light guide path 5 is formed to penetrate the holding member 8 in the front-rear direction X. This prevents, for example, scattered light emitted from the light-emitting unit 4 and scattered inside the tube 2 from leaking out in front of the imaging unit 3. If the scattered light described above leaks out in front of the imaging unit 3, the light intensity in front of the imaging unit 3 is likely to become unstable, so it is preferable to prevent the scattered light described above from leaking out from in front of the imaging unit 3. In addition, the second embodiment has the same functions and effects as the first embodiment.

[0061] (Summary of the embodiment) Next, the technical ideas grasped from the above-described embodiments will be described by using the reference numerals and the like in the embodiments. However, the reference numerals and the like in the following description do not limit the components in the claims to the members and the like specifically shown in the embodiments.

[0062] [1] An imaging unit 1 having at least an imaging section 3 whose outer casing 30 is rectangular when viewed from the front, a light-emitting section 4 located behind the imaging section 3 and emitting light toward the front, and a light guide path 5 located on the outer periphery of the imaging section 3 and guiding the light emitted from the light-emitting section 4 to a position forward of the imaging section 3, wherein the imaging unit 1 has two light-emitting sections 4, each of which emits light toward two adjacent sides of the rectangular imaging section 3.

[0063] [2] The imaging unit 1 described in [1], wherein each of the light-emitting units 4 has an elongated light-emitting surface 40 when viewed from the front, and both longitudinal ends of the light-emitting surface 40 of each of the light-emitting units 4 are arranged to extend beyond two adjacent sides of the rectangular imaging unit 3 when viewed from the front.

[0064] [3] The imaging unit 1 according to [1] or [2], wherein the light guide path 5 is made of a member that transmits light emitted by the light emitting section 4.

[0065] [4] The imaging unit 1 according to [3], wherein the light guide path 5 is configured by an optical fiber 51.

[0066] [5] An imaging unit 1 described in any one of [1] to [4], wherein, when viewed from the front, the light guide path 5 is arranged to fit within a virtual circumscribing circle C of the outer casing 30 of the imaging section 3.

[0067] [6] The imaging unit 1 described in any one of [1] to [5], further comprising: a tube 2 having the imaging unit 3 disposed inside; and a holding member 8 fitted into the tube 2 and having a holding hole 81 formed therein for inserting and holding the imaging unit 3.

[0068] [7] The imaging unit 1 described in [6], wherein the holding member 8 is made of a light-shielding member that blocks light emitted by the light-emitting unit 4, and the light guide path 5 is formed to penetrate the holding member 8 toward the front.

[0069] [8] The imaging unit 1 according to any one of [1] to [7], which is used in an endoscope 11.

[0070] (Variation) [A] An imaging unit 1 comprising: an imaging section 3 having a rectangular outer casing 30 when viewed from the front; a light emitting section 4 located behind the imaging section 3 and emitting light toward the front; and a light guide path 5 located on the outer periphery of the imaging section 3 and guiding the light emitted from the light emitting section 4 to a position forward of the imaging section 3, wherein when the directions along the outer casing 30 of the imaging section 3 when viewed from the front are defined as vertical and horizontal directions, the light guide path 5 is arranged on the vertical or horizontal side of the imaging section 3.

[0071] [B] The imaging unit 1 described in [A], wherein the light-emitting surface 40 of the light-emitting unit 4 is formed elongated in a direction inclined relative to the outer casing 30 of the imaging unit 3 when viewed from the front, the light-emitting surface 40 has a pair of protruding portions 41 that protrude from the imaging unit 3 on both sides in the longitudinal direction of the light-emitting unit 4 when viewed from the front, and the light guide path 5 guides light emitted from each of the pair of protruding portions 41 of the light-emitting surface 40 to the front of the imaging unit 3.

[0072] [C] The imaging unit 1 according to [A] or [B], wherein the light guide path 5 is made of a member that transmits light emitted by the light emitting section 4.

[0073] [D] The imaging unit 1 according to [C], wherein the light guide path 5 is configured by an optical fiber 51.

[0074] [E] An imaging unit 1 described in any one of [A] to [D], wherein, when viewed from the front, the light guide path 5 is arranged to fit within a virtual circumscribing circle C of the outer casing 30 of the imaging section 3.

[0075] [F] An imaging unit 1 described in any one of [A] to [E], further comprising: a tube 2 having the imaging unit 3 disposed inside; and a holding member 8 that is fitted into the tube 2 and has a holding hole 81 formed therein for inserting and holding the imaging unit 3.

[0076] [G] The imaging unit 1 described in [F], wherein the holding member 8 is made of a light-shielding member that blocks light emitted by the light-emitting unit 4, and the light guide path 5 is formed so as to penetrate the holding member 8 toward the front.

[0077] [H] The imaging unit 1 according to any one of [A] to [G], which is used in an endoscope 11.

[0078] In the imaging unit 1 described in modified example [A], the light guide path 5 is not arranged on an extension of the diagonal line of the outer casing 30 of the imaging section 3 when viewed from the front. If the light guide path 5 were arranged on the outer periphery of a corner of the outer casing 30 of the imaging section 3 when viewed from the front, the diameter of the imaging unit 1 would tend to increase, but the imaging unit 1 of this modified example can be made smaller and thinner. In this case, it does not matter whether the light-emitting section 4 is long or not.

[0079] (Addendum) Although the embodiments of the present invention have been described above, the invention according to the claims is not limited to the above-described embodiments. It should be noted that not all of the combinations of features described in the embodiments are necessarily essential to the means for solving the problems of the invention. Furthermore, the present invention can be appropriately modified and implemented within the scope of its spirit. [Explanation of symbols]

[0080] 1...Imaging unit 11...Endoscope 2...Tube 3...Image capture unit 30...Outer wall 4...Light emitting part 40...Light-emitting surface 41...protruding part 5...Light guide 51...Optical fiber 6...Cable 61…Coaxial line 62...Drain wire 63...Insulated wire 8...Retaining member 81...Retaining hole C…Circumcircle X…Axis direction

Claims

1. at least, When viewed from the front, the imaging unit has a rectangular outer shape, a light emitting unit located behind the imaging unit and emitting light toward the front; a light guide path located on the outer periphery of the imaging unit and guiding light emitted from the light emitting unit to a position forward of the imaging unit, The number of the light-emitting units is two, Each of the light emitting units emits light toward two adjacent sides of the rectangular imaging unit. Imaging unit.

2. Each of the light emitting units has an elongated light emitting surface when viewed from the front, each of the light-emitting units is disposed so that both ends in the longitudinal direction of the light-emitting surface thereof extend beyond two adjacent sides of the rectangular imaging unit when viewed from the front; The imaging unit according to claim 1 .

3. The light guide path is configured by a member that transmits light emitted by the light emitting unit. The imaging unit according to claim 1 or 2.

4. The light guide path is composed of an optical fiber. The imaging unit according to claim 3 .

5. When viewed from the front, the light guide path is arranged to be contained inside a virtual circumscribing circle of the outer contour of the imaging unit. The imaging unit according to claim 1 or 2.

6. a tube having the imaging unit disposed therein; a holding member that is fitted into the tube and has a holding hole formed therein into which the imaging unit is inserted and held; The imaging unit according to claim 1 or 2.

7. the holding member is made of a light-blocking member that blocks light emitted by the light-emitting unit, The light guide path is formed to penetrate the holding member toward the front. The imaging unit according to claim 6 .

8. Used in endoscopes, The imaging unit according to claim 1 or 2.

Images