JPS60225820A

JPS60225820A - Lighting optical system for endoscope

Info

Publication number: JPS60225820A
Application number: JP59082370A
Authority: JP
Inventors: Kimihiko Nishioka; 公彦西岡
Original assignee: Olympus Corp; Olympus Optical Co Ltd
Current assignee: Olympus Corp
Priority date: 1984-04-24
Filing date: 1984-04-24
Publication date: 1985-11-11

Abstract

PURPOSE:To optimize light distribution according to an observation range and to obtain uniform illumination by allowing light from a light emitting element to illuminate the observation range of an observation optical system through an optical element. CONSTITUTION:The light emitting element 11 is provided adjacently to the observation optical system of the endoscope and an illumination lens 12 is provided in front of the light emitting element 11. Thus, the light emitting element 11 and illumination lens 12 are provided adjacently to an observation lens and the observation range is illuminated by the light emitting element; a light guide which is required before is not necessary and the operativity of the endoscope is improved. Further, plural light emitting elements are provided to obtain uniform illumination; and plural light emitting elements are provided irregularly and light emitting elements which do not contribute to the illumination of the observation range are turned off according to observation distance to obtain optimum light distribution.

Description

【発明の詳細な説明】技術分野本発明は、発光素子を用いた内視鏡用照明光学系に関す
る。DETAILED DESCRIPTION OF THE INVENTION Technical Field The present invention relates to an illumination optical system for an endoscope using a light emitting element.

従来技術従来内視鏡は第２図に示したように構成されており、１
は内視鏡、２は先端部、３は湾曲部、４は軟性部、５は
操作部、６はイメージガイド、７は先端部２内でイメー
ジガイド６０入射端に対向して配設された観察レンズ、
８はライトガイド、９はライト）゛イド８の入射端に設
けられた光源装置、１０は先端部２内でライトガイド８
の射出端に対向して配設された照明レンズであり、操作
部５に設けられたファインダーを覗くことによシ観察を
行なうようになっている。しかしながら、仁の構成にお
いては、ライトガイドが外部の光源装置に接続されてい
るため操作性が悪く、また照明光学系による照明光は、
遠点被写体観察時にも近点被写体観察時にも常に一定で
あり、特に近点被写体を観察する場合には観察光学系に
よる観察範囲と照明光学系による照明範囲との間にずれ
が生じてしまい、さらに観察範囲の均一な照明を得るこ
とは困難であった。Prior Art A conventional endoscope is constructed as shown in Fig. 2.
2 is an endoscope, 2 is a distal end, 3 is a curved part, 4 is a flexible part, 5 is an operating part, 6 is an image guide, and 7 is disposed within the distal end 2 facing the image guide 60 entrance end. observation lens,
Reference numeral 8 indicates a light guide, 9 indicates a light source device provided at the input end of the light guide 8, and 10 indicates a light guide 8 within the tip portion 2.
This is an illumination lens disposed opposite the exit end of the control unit 5, and is designed to be observed by looking through a finder provided in the operation unit 5. However, in the Jin configuration, the light guide is connected to an external light source device, making it difficult to operate, and the illumination light from the illumination optical system is
It is always constant both when observing a far-point object and when observing a near-point object, and especially when observing a near-point object, a deviation occurs between the observation range by the observation optical system and the illumination range by the illumination optical system. Furthermore, it was difficult to obtain uniform illumination of the observation range.

目　的本発明は、以上の点に鑑み、光源として発光素子を用い
ることによりライトガイドを排除して操作性を良くシ、
さらに観察範囲に応じて配光を最ｉ　適“し得４と共に
観察範囲と照明範囲と０ずれをなくシ、且つ均一な照明
を得るようにした内視鏡用照明光学系を提供することを
目的としている。Purpose In view of the above points, the present invention uses a light emitting element as a light source to eliminate the light guide and improve operability.
Furthermore, it is an object of the present invention to provide an illumination optical system for an endoscope that can optimally distribute light according to the observation range, eliminate zero deviation between the observation range and the illumination range, and obtain uniform illumination. The purpose is

概要この目的は、観察光学系に隣接して配設された発光素子
と、該発光素子の前に配設された少なくとも一枚の照明
レンズ捷たはプリズムの如き光学要素とから構成されて
いて、該発光素子から出た光が該光学要素を介して観察
光学系による観察範囲を照明するようにしたことを特徴
とする、内視鏡用照明光学系により解決される。Overview This object consists of a light emitting element disposed adjacent to the observation optical system and at least one optical element such as an illumination lens or prism disposed in front of the light emitting element. This problem is solved by an illumination optical system for an endoscope, characterized in that light emitted from the light emitting element illuminates an observation range by the observation optical system via the optical element.

実施例以下図面に示した実施例に基づき本発明を説明すれば、
先づ第１図において、ｌｌは内視鏡の観察光学系に隣接
して例えば従来のライトガイド射出端の位置に配設され
た発光素子、１２は発光素子１１の前に配設された照明
レンズであって、このように構成された照明光学系によ
れば、ライトガイドが不要になり、内視鏡の操作性が向
上する。EXAMPLES The present invention will be explained based on examples shown in the drawings below.
First, in FIG. 1, 11 is a light emitting element arranged adjacent to the observation optical system of the endoscope, for example at the exit end of a conventional light guide, and 12 is an illumination arranged in front of the light emitting element 11. According to the lens illumination optical system configured in this way, a light guide is not required, and the operability of the endoscope is improved.

第３図は照明レンズ１２０代シにプリズム１３を配設し
た実施例であり、発光素子１１から出た光はプリズム１
３により観察光学系側へ屈折せしめられ、かくして観察
光学系による観察範囲が有効に照明され得る。第４図で
は複数個の発光素子１４が照明レンズ１５に対して同心
円周上に配設されておシ、この構成によれば、第５図に
実線で示したように広い範囲に亘って均一な照明が得ら
れる（尚、第１図及び第３図による照明光量分布が点線
によシ示されている。）。第６図においては、複数個の
発光素子１６が凹レンズとして形成された照明レンズ１
７に対して同心円周上に図示の如く不均一に配設されて
おシ、例えば近点被写体観察時に観察範囲の照明に寄与
しない発光素子１６はＯＦＦにし得る。FIG. 3 shows an embodiment in which a prism 13 is disposed on the illumination lens 120, and the light emitted from the light emitting element 11 is transmitted through the prism 1.
3, the light is refracted toward the observation optical system, and thus the observation range by the observation optical system can be effectively illuminated. In FIG. 4, a plurality of light emitting elements 14 are arranged concentrically with respect to the illumination lens 15. According to this configuration, the light emitting elements 14 are uniformly distributed over a wide range as shown by the solid line in FIG. (Note that the illumination light intensity distribution in FIGS. 1 and 3 is shown by dotted lines.) In FIG. 6, the illumination lens 1 has a plurality of light emitting elements 16 formed as concave lenses.
The light emitting elements 16, which are non-uniformly arranged as shown in the figure on a concentric circle with respect to the light emitting element 7, and which do not contribute to the illumination of the observation range during near-point object observation, can be turned off.

第７図は本発明を側視型内視鏡に適用した場合の一実施
例を示しておシ、２′は内視鏡先端部、６′はイメージ
ガイド、７′はイメージガイド６′の入射端に対向して
配設された観察レンズ、ＩＯ′は観察レンズ７′に隣接
して配設された照明レンズ、１８は照明レンズ１０′の
後方に例えば第７図（Ｂ）に示したように配設された発
光素子で、被写体までの距離に応じて最適な照明光が得
られるように発光すべき発光素子１８が選択されるよう
になっている。FIG. 7 shows an embodiment in which the present invention is applied to a side-viewing endoscope, where 2' is the tip of the endoscope, 6' is the image guide, and 7' is the image guide 6'. An observation lens disposed opposite the incident end, IO' an illumination lens disposed adjacent to the observation lens 7', and IO' an illumination lens 18 located behind the illumination lens 10' as shown in FIG. 7(B), for example. Among the light emitting elements arranged in this way, the light emitting element 18 to emit light is selected so as to obtain the optimum illumination light according to the distance to the subject.

このような構成によれば、側視型内視鏡では被写体との
距離が極端に近くなることがあるがそのときにも観察視
野が有効に照明され得るように発光素子１８が選択的に
発光せしめられる。With this configuration, the light emitting element 18 selectively emits light so that the observation field can be effectively illuminated even when the distance to the subject may become extremely short in a side-viewing endoscope. I am forced to do it.

第８図はイメージガイドを使用せずに観察レンズ７の後
方に固体撮像素子２０を配設した内視鏡に本発明を適用
した場合を示しておシ、２１は照明レンズ、２２は照明
レンズ２１の後方に配設された複数個の発光素子、２３
は発光素子用電源で、さらに２４は固体撮像素子２０の
出力に基づき該固体撮像素子２０上における観察像の光
量及び光量分布を測定するための測定回路であり、この
測定結果に基づいて発光素子２２の各々の明るさが電源
２３によシ独立的に調節されるようになっている。この
構成によれば、各発光素子２２の明るさが独立的に調節
されることによシ、遠点被写体観察時にも近点被写体観
察時にも最適な照明の配光が得られ、また常に均一な照
明が行なわれ得る。FIG. 8 shows a case where the present invention is applied to an endoscope in which a solid-state image sensor 20 is arranged behind the observation lens 7 without using an image guide, where 21 is an illumination lens, and 22 is an illumination lens. A plurality of light emitting elements arranged behind 21, 23
24 is a power source for the light-emitting device, and 24 is a measurement circuit for measuring the light amount and light amount distribution of the observed image on the solid-state image sensor 20 based on the output of the solid-state image sensor 20. The brightness of each of 22 is adjusted independently by a power source 23. According to this configuration, by adjusting the brightness of each light emitting element 22 independently, an optimal light distribution can be obtained both when observing a far-point object and when observing a near-point object, and it is always uniform. lighting can be performed.

さらに、第９図に示されているように、（Ａ）の如く発
光素子の配光が中心の最大光量の−となる角度（ｒ　（
Ｂ）に示したようにθｈとし、照明光学系の光軸から発
光素子までの距離をり、照明レンズの焦点距離をｆとし
たとき、該照明レンズの屈折角はよシ、発光素子からの
角度θｈ以下の光は照明レンズ内で全反射することなく
すべて照明に寄与することになシ、かくして発光素子か
らの光が有効に観察光学系による観察範囲を照明する。Furthermore, as shown in FIG. 9, the angle (r (
As shown in B), when θh is the distance from the optical axis of the illumination optical system to the light emitting element, and the focal length of the illumination lens is f, the refraction angle of the illumination lens is All of the light below the angle θh contributes to illumination without being totally reflected within the illumination lens, and thus the light from the light emitting element effectively illuminates the observation range by the observation optical system.

尚、以上の説明において発光素子としてはＬＥｐ　。In addition, in the above description, LEp is used as a light emitting element.

半導体レーザー、ランプ等が使用され得、異なる色の即
ち二色以上の発光素子によシ異なる色の照明光を切換使
用するようにしてもよく、また照明レンズとしては非球
面レンズまたは屈折率勾配型レンズを使用し得ることは
いうまでもない。Semiconductor lasers, lamps, etc. may be used, and illumination light of different colors may be switched and used by light emitting elements of different colors, that is, two or more colors, and an aspherical lens or a refractive index gradient may be used as the illumination lens. It goes without saying that mold lenses can be used.

発明の効果以上述べたように本発明によれば、観察レンズ１　に隣
接して発光素子及び照明レンズを配設して該発光素子に
より観察範囲を照明するようにしたから、ライトガイド
が不要になるため内視鏡の操作性が向上し、また複数個
の発光素子を備えることにより均一な照明が得られ、さ
らに複数個の発光素子を不均一に配設することによシ観
察距離に応じて観察範囲の照明に寄与しない発光素子を
ＯＦＦにして最適な配光が実現され、また観察像の光量
及び光量分布に基づいて各発光素子の明るさが独立的に
調節されることにより最適な光量及び光量ことにより発
光素子からの光が有効に照明に寄与することになり、か
くして観察光学系による観察範囲が常に有効に照明され
得、極めて効果的である。Effects of the Invention As described above, according to the present invention, a light emitting element and an illumination lens are disposed adjacent to the observation lens 1, and the observation range is illuminated by the light emitting element, thereby eliminating the need for a light guide. This improves the operability of the endoscope, and by providing multiple light emitting elements, uniform illumination can be obtained.Furthermore, by arranging the multiple light emitting elements non-uniformly, the endoscope can be illuminated according to the observation distance. The optimum light distribution is realized by turning off the light emitting elements that do not contribute to the illumination of the observation range, and the brightness of each light emitting element is independently adjusted based on the light intensity and light intensity distribution of the observed image. Due to the amount of light and the amount of light, the light from the light emitting element effectively contributes to illumination, and thus the observation range by the observation optical system can always be effectively illuminated, which is extremely effective.

【図面の簡単な説明】[Brief explanation of drawings]

第１図は本発明による内視鏡用照明光学系の一実施例の
概略図、第２図は従来の内視鏡の一例を示す概略断面図
、第３図及び第４図は本発明による他の実施例を示す概
略図、第５図は第４図の実施例における照明光量分布を
示すグラフ、第６図。第７図、第８図及び第９図はさらに他の実施例を示す概
略図である。ｌ・・・・内視鏡、２．２′・・・・先端部、３・・・
・湾曲部、４・・・・軟性部、５・・・・操作部、６，
６′・・・・イメージガイド、７．７’・・・・観察レ
ンズ、８・・・・ライトガイド、９・・・・光源装置、
１０．１０’、１２゜１５．１７．２１・・・・照明レ
ンズ、１１．１４゜１６．１８．２２・・・・発光素子
、１３・・・・プリズム、２０・・・・固体撮像素子、
２３・・・・電源、２４・・・・測定回路。１１図　５ｊ−３図２１３第４図（Ａ）（８）第５図１６図（Ａ）　（Ｂ）３−７図（Ｂ）FIG. 1 is a schematic diagram of an embodiment of an endoscope illumination optical system according to the present invention, FIG. 2 is a schematic sectional view showing an example of a conventional endoscope, and FIGS. 3 and 4 are according to the present invention. FIG. 5 is a schematic diagram showing another embodiment, and FIG. 6 is a graph showing the illumination light amount distribution in the embodiment of FIG. 4. FIG. 7, FIG. 8, and FIG. 9 are schematic diagrams showing still other embodiments. l...Endoscope, 2.2'...Tip, 3...
- Curved part, 4... Soft part, 5... Operation part, 6,
6'... Image guide, 7.7'... Observation lens, 8... Light guide, 9... Light source device,
10.10', 12゜15.17.21...Illumination lens, 11.14゜16.18.22...Light emitting element, 13...Prism, 20...Solid-state imaging device ,
23...Power supply, 24...Measurement circuit. Figure 11 Figure 5j-3 Figure 213 Figure 4 (A) (8) Figure 5 Figure 16 (A) (B) Figure 3-7 (B)

Claims

【特許請求の範囲】[Claims]

（１）観察光学系に隣接して配設された発光素子と、該
発光素子の前に配設された少なくとも一枚の照明レンズ
またはプリズムの如き光学要素とから構成されていて、
該発光素子から出た光が該光学要素を介して観察光学系
による観察範囲を照明するようにしたことを特徴とする
、内視鏡用照明光学系。(1) Consisting of a light emitting element disposed adjacent to the observation optical system and at least one optical element such as an illumination lens or prism disposed in front of the light emitting element,
An illumination optical system for an endoscope, characterized in that light emitted from the light emitting element illuminates an observation range by the observation optical system via the optical element.

（２）複数個の発光素子が配設されていることを特徴と
する特許請求の範囲（１）に記載の内視鏡用照明光学系
。(2) The illumination optical system for an endoscope according to claim (1), characterized in that a plurality of light emitting elements are arranged.

（３）複数個の発光素子が不均一に配設されていること
を特徴とする特許請求の範囲（１）に記載の内視鏡用照
明光学系。(3) The illumination optical system for an endoscope according to claim (1), wherein a plurality of light emitting elements are arranged non-uniformly.

（４）観察像の光量及び光量分布に基づいて各発光素子
の明るさが独立的に調節されるようにした？）−ｂａ指
Ｊ−ナス　慇杵請すの節回（１）嘴、戯１１１の何れか
に記載の内視鏡用照明光学系。(4) Was the brightness of each light emitting element adjusted independently based on the light amount and light amount distribution of the observed image? )-ba finger J-egglet The illumination optical system for an endoscope according to any one of paragraphs (1) and 111.

（５）照明光学系の光軸から発光素子までの距離をり、
照明レンズの焦点距離ｆ、ｆ、発光素子の配光が中心の
最大光量の−となる角度をθｈとしたとき、の条件式を満たすことを特徴とする特許請求の範囲（１
）から（４）の何れかに記載の内視鏡用照明光学系。(5) Calculate the distance from the optical axis of the illumination optical system to the light emitting element,
The scope of claim 1 is characterized in that the conditional expression (1) is satisfied when the focal lengths of the illumination lenses are f and f, and the angle at which the light distribution of the light emitting element is - from the maximum light amount at the center is θh.
) to (4).