A stereoscopic endoscope includes a sheath for insertion into the body of a patient and a pair of image guides and an illumination or light guide extending through the sheath. The image guides and light guide are preferably formed of optical fibers to facilitate flexibility of the endoscope. The image guides optically connect with a stereoscopc viewer for three dimensional viewing of a site within the body. The viewer includes couplings for attaching miniaturized video cameras, the cameras in turn being connected to a head worn stereoscopic video display. In addition, the video signals representing the images gathered by the endoscope may be displayed on remote monitors or recorded by a video recorder. The endoscope may include other channels extending through the sheath such as water, air, gas, other fluid channels with associated valves and/or a channel for receiving an endoscopic surgical tool.

Stereoscopic endoscope arrangement

An endoscope for stereo-optically viewing an object comprises a tubular insertion portion (6A, 6B) characterized by a pair of adjacent asymmetric optical systems including a primary imaging channel (10) and a secondary imaging channel (12). Associated with each channel is a solid state electronic imaging means (68, 80) positioned to receive the images relayed by primary and secondary image-relaying means. The optical portion of the primary channel comprises a relatively large objective lens system (20) and a primary image relaying means (22) designed to provide sharply focussed first images. The optical portion of the secondary channel comprises a relatively small diameter objective lens system (24A) and a secondary image relaying means (26A) designed to relay enough light and image information to provide an acceptable stereoscopic capability.

Asymmetric stereo-optic endoscope

A laser utilizes a cavity design which allows the stable generation of high peak power pulses from mode-locked multi-mode fiber lasers, greatly extending the peak power limits of conventional mode-locked single-mode fiber lasers. Mode-locking may be induced by insertion of a saturable absorber into the cavity and by inserting one or more mode-filters to ensure the oscillation of the fundamental mode in the multi-mode fiber. The probability of damage of the absorber may be minimized by the insertion of an additional semiconductor optical power limiter into the cavity.

Mode-locked multi-mode fiber laser pulse source

A stereoscopic objective lens system for video endoscopes and borescopes includes a full diameter collimator lens system (110, 112) and a pair of half-diameter stereo lens systems (114, 116, 118, 120). The lens systems can be formed of doublet lenses (312) or a combination of singlet (310, 313) and doublet lenses (312, 314, 318), or of gradient index lenses (210, 214, 216) or of a mixture of such lenses. The full-diameter lens system collimates object points, imaging object points to infinity to present equal-angle pairs from symmetrically disposed object points to the small stereo pair. This equal-angle property enables accurate object/image mapping onto the final stereo image pair, such that all parts of each left/right image can be mapped to within a fraction of a video pixel to each other.

Stereo video endoscope objective lens system

An imaging system includes a pulsed laser, a pre-compensator for chromatic dispersion, a transmission optical fiber, and a GRIN lens. The pre-compensator chirps optical pulses received from the laser. The transmission optical fiber transports the chirped optical pulses from the pre-compensator. The GRIN lens receives the transported optical pulses from the transmission optical fiber. The GRIN lens has a wider optical core than the transmission optical fiber and substantially narrows the transported optical pulses received from the transmission optical fiber.

Multi-photon endoscopic imaging system

A current-measuring system comprises a fiberlike light guide capable of causing the Faraday effect. The guide is adapted to be placed in proximity to a current-carrying conductor. Polarized light is applied to one end of the guide, and the output of the guide is applied to an analyzer and a detector, thereby to provide an indication of the magnitude of the current flow in the conductor.

Current-measuring system utilizing faraday effect element

The invention contemplates an improved light-mode separator for orientation in axially offset adjacency to an end of an optical fiber, in a plane perpendicular to the fiber axis; separate concentric regions of the separator about the fiber axis have different light-converging properties such that the convergence point for each light-converging region is (a) offset with respect to the convergence point for each remaining light-converging region, and is also (b) independently externally accessible for focused-energy utilization without masking interference with any other converging light from the separator.

Mode separator and delay equalizer for multimode optical fiber transmission systems

The disclosure relates to an optical image transmitting apparatus adapted for a viewfinder for observation of any object, wherein two systems of transparent structures are provided whose refractive index distribution in each cross section perpendicular to the center axis is reduced nearly in proportion to a square of a distance from the center axis, said transparent structures consisting of rod-like or fibrous substance and being disposed so as to view any article stereoscopically; a viewfinder for medical observation wherein said transparent structures cable of transmitting an optical image therethrough and an optical fiber boundle for transmitting an illumination light to illuminate the article to be the observed are provided in a cavity portion of the inside of a hollow needle such as a hypodermic syringe; a microscope wherein said fibrous transparent structures are used as the object lens; and the like.

Streoscopic microscope with graded index fiber objective lenses

A pulse modulation driver circuit for a semiconductor laser is disclosed which discriminates among input pulse signals composed of binary codes to detect the occurrence of a pulse having a code of '''' 1'''' following a pulse having a code of ''''0''''. Detection of this pattern is used to control the driver to increase either or both the width or peak value of the pulse having a code of 1. The effect of this is to eliminate a pattern effect in the light emitted by the semiconductor laser caused by an attenuation of the population inversion in the laser.

Driver circuit for pulse modulation of a semiconductor laser

A noise suppression optical filter having practical utility in increasing the signal-to-noise ratio of a laser communication system. The filter comprises a converging light guide element having an index of refraction which varies inversely with the square of the distance from the central axis. Irises having apertures of specified diameters are located at the input and output ends of that light guide, and means are provided to position these apertures in alignment with the light travelling through the guide.

Atsufumi Ueki

Papers

Current-measuring system utilizing faraday effect element

Mode separator and delay equalizer for multimode optical fiber transmission systems

Streoscopic microscope with graded index fiber objective lenses

Driver circuit for pulse modulation of a semiconductor laser

Optical filter for suppressing noise which utilizes a graded optical fiber and means for controlling transverse position of iris