JP2007020824A - Imaging part of electronic endoscope - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an imaging part of an electronic endoscope which does not generate the degradation or damages or the like of an imaging surface when heated inside an autoclave device or the like even when it is the imaging part of the electronic endoscope structured such that a solid-state imaging element unit of an independently tightly sealed structure is attached to the rear end part of an objective optical system unit. <P>SOLUTION: In the imaging part of the electronic endoscope provided with the solid-state imaging element unit 10 structured such that the imaging surface 11a is airtightly sealed with cover glass 14 arranged facing it and is independently tightly closed as a unit and the objective optical system unit 9 structured such that the distal end part is airtightly sealed with a first lens 41 and the rear side part is airtightly sealed with the solid-state imaging element unit 10 and tightly closed, a gas is enclosed in the internal space P of the solid-state imaging element unit 10 by an air pressure lower than the atmospheric pressure at a normal temperature. <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

  The present invention relates to an imaging unit of an electronic endoscope.

  In an electronic endoscope, an imaging surface of a solid-state imaging device is disposed at a projection position of a subject by an objective optical system built in the distal end of an insertion portion, and when stored in an autoclave (high-temperature high-pressure steam sterilization) apparatus, In order not to enter the optical path or the like, a seal structure is employed in the optical system and the solid-state imaging device.

And in order to prevent the pressure in the space in the seal portion from increasing due to heating in the autoclave device and damaging the seal portion, the space in the seal portion is 0.7 to lower than atmospheric pressure at room temperature. Gas is sealed at 0.8 atm (for example, Patent Document 1).
JP 2000-126113 A

  In the invention described in Patent Document 1, the entire space including the objective optical system and the solid-state imaging device is collectively sealed with respect to its surroundings. However, in reality, the solid-state imaging device is unitized separately from the objective optical system, and the imaging surface of the solid-state imaging device is hermetically sealed by a cover glass disposed opposite thereto, so that the solid-state imaging device unit is independent. Normally, it has a sealed structure.

  Therefore, when such a solid-state image sensor unit having a sealed structure is assembled at the rear end portion of the objective optical system having an internal space lower than the atmospheric pressure at room temperature, the object is detected when heated in the autoclave apparatus. Although there is no problem in the optical system portion, there is a risk that the microlens and the color filter disposed on the imaging surface of the solid-state imaging device will be deteriorated or damaged due to the pressure increase in the solid-state imaging device unit.

  In view of this, the present invention provides a solid-state imaging device unit having a sealed structure alone, which is heated in an autoclave apparatus even in an imaging unit of an electronic endoscope having a structure attached to the rear end of the objective optical system unit. An object of the present invention is to provide an imaging unit of an electronic endoscope that does not cause deterioration or breakage of the imaging surface at times.

  In order to achieve the above object, the imaging unit of the electronic endoscope of the present invention has a solid-state imaging structure in which the imaging surface is hermetically sealed by a cover glass disposed opposite to the imaging surface and sealed as a unit. An electronic endoscope having an element unit and an objective optical system unit having a structure in which a front end portion is hermetically sealed by a first lens and a rear portion is hermetically sealed by a solid-state imaging element unit In the imaging unit, a gas is sealed in the internal space of the solid-state imaging device unit at a normal temperature and lower than atmospheric pressure.

  Note that gas may be sealed in the internal space of the objective optical system unit at a pressure lower than atmospheric pressure at room temperature. In this case, the atmospheric pressure in the solid-state image sensor unit and the atmospheric pressure in the objective optical system unit are almost equal. It is good to be.

  According to the present invention, a solid-state image pickup unit having a sealed structure is provided at the rear end of the objective optical system unit by sealing a gas in the internal space of the solid-state image pickup unit at an atmospheric pressure lower than atmospheric pressure at room temperature. Even in the image pickup section of the electronic endoscope having the attached structure, even if the pressure in the internal space of the solid-state image pickup device unit is increased by being heated in the autoclave device, the image pickup surface is not deteriorated or damaged.

  A solid-state imaging device unit having a structure in which an imaging surface is hermetically sealed by a cover glass disposed opposite to the unit and hermetically sealed as a unit, and a front end portion is hermetically sealed by a first lens, and a rear portion is In an imaging part of an electronic endoscope provided with an objective optical system unit that is hermetically sealed by a solid-state image sensor unit, an atmospheric pressure lower than atmospheric pressure at room temperature in the internal space of the solid-state image sensor unit Fill the gas with.

Embodiments of the present invention will be described with reference to the drawings.
FIG. 2 shows the distal end portion of the insertion portion 1 of the electronic endoscope. On the distal end surface of the distal end portion main body 2 connected to the distal end of the insertion portion 1, an observation window 3, a treatment instrument protruding port 4, and the like are illustrated. There are no lighting windows etc. Reference numeral 5 denotes a treatment instrument insertion channel that is inserted through the entire length of the insertion portion 1.

  A first lens 41 in an objective optical system including a plurality of objective lenses 41 to 45 is fitted in the observation window 3, and the imaging surface 11 a of the solid-state imaging device 11 is disposed at the projection position of the subject by the objective optical system. Has been.

  A signal line 21 of a signal cable 20 that is inserted through the entire length of the insertion portion 1 is connected to a connection terminal 15 that protrudes rearward from the insulating base 12 that holds the solid-state imaging device 11.

  In the objective optical system, as shown in FIG. 3 which is an enlarged view of the objective optical system, all objective lenses 41 to 45 are mounted in a cylindrical objective lens barrel 40 so that the optical axes thereof coincide with each other. It is formed as a unit, and the distance between the objective lenses 41 to 45 is regulated by the spacer 6.

  The first lens 41 of the objective optical system is airtightly bonded to the inner peripheral surface of the tip portion of the objective lens barrel 40 by, for example, an inorganic adhesive or the like (airtight junction A), whereby the tip portion of the objective lens barrel 40 is It is hermetically sealed. A unit connection hole 7 into which the solid-state imaging element unit 10 is inserted is formed at the rear end of the objective barrel 40.

  The solid-state image sensor 11 is bonded and fixed to the front surface of a block-shaped insulating base 12 made of an electrical insulating material such as ceramic as shown in FIG. Yes. Electrical wiring and electronic components are built in the insulating base 12, and the connection terminals 15 protrude rearward from the rear end of the insulating base 12. Reference numeral 16 denotes a lead frame for transmitting an electrical signal.

  Then, the inner peripheral surface of the rear end portion of the metallic cylindrical element unit housing 13 provided so as to surround the periphery of the insulating base 12 extends to the outer peripheral surface of the insulating base 12 over, for example, welding, brazing or adhesion. Airtightly joined (airtight joint B), the front end of the element unit housing 13 is in contact with the vicinity of the outer edge of the front surface of the solid-state imaging device 11.

  The front end portion of the element unit housing 13 has a transparent parallel flat plate shape so that a portion facing the imaging surface 11a is a window so as not to cover the imaging surface 11a of the solid-state imaging device 11, and the window is closed. The cover glass 14 is airtightly bonded over the entire periphery with an inorganic adhesive or the like (airtight bonding portion C), and is in a state of facing the imaging surface 11a.

  As a result, the solid-state image sensor unit 10 is hermetically sealed by the element unit housing 13 and the cover glass 14, and has a structure that is hermetically sealed as a whole unit. In addition, air or an inert gas (or other gas) having a pressure lower than the atmospheric pressure, for example, about 0.7 atmospheric pressure at normal temperature is enclosed.

  As shown in FIG. 1, the solid-state imaging device unit 10 having such a sealed structure is fitted into the unit connection hole 7 formed at the rear end of the objective barrel 40 of the objective optical system unit 9. The outer peripheral surface of the element unit housing 13 is airtightly joined to the inner peripheral surface of the unit connection hole 7 by, for example, an inorganic adhesive (airtight joint D).

  Accordingly, the objective optical system unit 9 has a structure in which the front end portion is hermetically sealed by the first lens 41 and the rear side portion is hermetically sealed by the solid-state imaging element unit 10 so that the entire unit is hermetically sealed. In this embodiment, the internal space Q is sealed with air having an atmospheric pressure equal to the atmospheric pressure at room temperature.

  The imaging unit of the electronic endoscope according to the embodiment configured as described above has a structure in which the objective optical system unit 9 and the solid-state imaging device unit 10 are independently and hermetically sealed, and the solid-state imaging device. Since the internal space P of the unit 10 is lower than atmospheric pressure at room temperature, the gas in the solid-state image sensor unit 10 is heated when heated in the autoclave device for sterilization after use of the endoscope. Even if it expands, the inside of the solid-state image sensor unit 10 does not become a high pressure, so that the microlens, the color filter, and the like arranged on the imaging surface 11a are not deteriorated or damaged.

  FIG. 5 shows a second embodiment of the present invention, in which the objective optical system unit 9 and the solid-state image sensor unit 10 are independently and hermetically sealed, and the solid-state image sensor unit. The ten internal spaces P are completely the same as the first embodiment described above in that the atmospheric pressure is lower than atmospheric pressure at room temperature.

  In this embodiment, the internal space Q of the objective optical system unit 9 is also filled with gas at the same room temperature as that in the solid-state imaging device unit 10 at a pressure of about 0.7 atm. As a result, in the autoclave apparatus Even if the gas in the objective optical system unit 9 and the solid-state image sensor unit 10 is thermally expanded by being heated at, damage to the cover glass 14 can be prevented.

It is side surface sectional drawing of the imaging part of the electronic endoscope of 1st Example of this invention. It is side surface sectional drawing of the front-end | tip part of the insertion part of the electronic endoscope of 1st Example of this invention. It is side surface sectional drawing of the state by which the imaging part of the electronic endoscope of 1st Example of this invention was divided according to the unit. It is side surface sectional drawing of the solid-state image sensor unit of the imaging part of the electronic endoscope of 1st Example of this invention. It is side surface sectional drawing of the imaging part of the electronic endoscope of 2nd Example of this invention.

Explanation of symbols

DESCRIPTION OF SYMBOLS 9 Objective optical system unit 10 Solid-state image sensor unit 11 Solid-state image sensor 11a Image pick-up surface 12 Insulating base 13 Element unit housing 14 Cover glass 40 Objective lens 41-45 Objective lens 41 1st lens A-D Airtight junction P Solid-state image sensor Internal space of the unit Q Internal space of the objective optical system unit

Claims (3)

A solid-state imaging device unit having a structure in which an imaging surface is hermetically sealed by a cover glass disposed opposite to the unit and hermetically sealed as a unit, and a front end portion is hermetically sealed by a first lens, and a rear portion is In an imaging unit of an electronic endoscope provided with an objective optical system unit having a structure hermetically sealed by the solid-state imaging element unit,
An imaging part of an electronic endoscope, wherein a gas is sealed in an internal space of the solid-state imaging element unit at an atmospheric pressure lower than atmospheric pressure at room temperature.   The imaging part of the electronic endoscope according to claim 1, wherein a gas is sealed in an internal space of the objective optical system unit at a normal temperature and lower than atmospheric pressure.   The imaging unit of the electronic endoscope according to claim 1 or 2, wherein the atmospheric pressure in the solid-state imaging device unit and the atmospheric pressure in the objective optical system unit are substantially equal.

Images