US 2002/0161278 A1Published application

Endoscope apparatus

AssigneeOlympus Optical Co., Ltd.

InventorMinoru Nakamura

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Abstract

An endoscope apparatus has an object optical system to conduct measurements or stereoscopic-vision observations. The object optical system arranges in order from an object side to an image side, a first unit, a second unit, a third unit, and an image pickup unit. The first unit includes a negative lenses, the second unit includes a first positive lenses, wherein the first positive lenses forms no real image within the second and third units. The third unit includes a second positive lenses, and the image pickup unit includes a single image pick up device.

Claims20

Dependent claims

An endoscope apparatus having an insertion part which includes an object optical system to conduct measurements or stereoscopic-vision observations, said object optical system comprising:

in turn from an object side to an image side, a first unit, a second unit, a brightness diaphragm, a third unit, and an image pickup unit;
wherein said first unit includes an object cover glass, a pair of negative lenses arranged in parallel and almost in contact with each other, and a pair of field masks corresponding to said pair of negative lenses, respectively, wherein a principal ray emergent to said image side in each of said pair of negative lenses is parallel to each optical axis of said pair of negative lenses;
said second unit including a flare mask having an analogous form which corresponds to the range of said field mask, and a first positive lenses having an optical axis which is positioned eccentrically to at least one of the optical axes of said pair of negative lenses, wherein said first positive lenses forms no real image within said second and third units;
said brightness diaphragm including a single aperture section and an adapter cover glass, said brightness diagram being positioned at a back-focus-position of said first positive lenses of said second unit, wherein each optical axis of said pair of negative lenses passes through said single aperture section, said single aperture section being positioned unitarily with said adapter cover glass;
said third unit including a master cover glass, and a second positive lenses capable of focusing on an infinity-distance-object, wherein the following equation (1) is satisfied as a condition to enable said second positive lenses to focus on the infinity-distance-object:
|φa/φ|<1 (1)
where φa is a combined power of said first unit and said second unit, and φ is a combined power of said first to third units;
and
said image pickup unit including an infrared cut off filter, and an image pickup device positioned at a back-focus-position of said second positive lenses of said third unit, said image pickup device being single and having 2 to 2.5 mm or less of effective image pickup range;
and
wherein said first unit, said second unit, and said brightness diaphragm are comprised in an adapter so as to be detachable from said third unit and said image pickup unit at a boundary between said adapter cover glass and said master cover glass.

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Dependencies are inferred from the claim text.

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Abstract

An endoscope apparatus having an insertion part which includes an object optical system to conduct measurements or stereoscopic-vision observations, said object optical system comprising:

in turn from an object side to an image side, a first unit, a second unit, a brightness diaphragm, a third unit, and an image pickup unit;
wherein said first unit includes an object cover glass, a pair of negative lenses arranged in parallel and almost in contact with each other, and a pair of field masks corresponding to said pair of negative lenses, respectively, wherein a principal ray emergent to said image side in each of said pair of negative lenses is parallel to each optical axis of said pair of negative lenses;
said second unit including a flare mask having an analogous form which corresponds to the range of said field mask, and a first positive lenses having an optical axis which is positioned eccentrically to at least one of the optical axes of said pair of negative lenses, wherein said first positive lenses forms no real image within said second and third units;
said brightness diaphragm including a single aperture section and an adapter cover glass, said brightness diagram being positioned at a back-focus-position of said first positive lenses of said second unit, wherein each optical axis of said pair of negative lenses passes through said single aperture section, said single aperture section being positioned unitarily with said adapter cover glass;
said third unit including a master cover glass, and a second positive lenses capable of focusing on an infinity-distance-object, wherein the following equation (1) is satisfied as a condition to enable said second positive lenses to focus on the infinity-distance-object:
|φa/φ|<1 (1)
where φa is a combined power of said first unit and said second unit, and φ is a combined power of said first to third units;
and
said image pickup unit including an infrared cut off filter, and an image pickup device positioned at a back-focus-position of said second positive lenses of said third unit, said image pickup device being single and having 2 to 2.5 mm or less of effective image pickup range;
and
wherein said first unit, said second unit, and said brightness diaphragm are comprised in an adapter so as to be detachable from said third unit and said image pickup unit at a boundary between said adapter cover glass and said master cover glass.

8 more elements