The objective lens unit includes, a front lens group having a negative refractive power, a diaphragm, and a rear lens group having a positive refractive power, in order from an object side. The front lens group includes a negative lens having a concave surface facing an image surface side, and a positive lens having a convex surface facing the object side, and the rear lens group includes a positive lens having a convex surface facing the image surface side and a cemented lens in which a positive lens and a negative lens are cemented. The endoscope objective lens unit satisfies 1.6<f.sub.F/f.sub.R<1.2 and 1.3<f.sub.3/f.sub.F<0.7. Note that f.sub.F and f.sub.R are focal lengths of the entire system of the front lens group and the rear lens group, and f.sub.3 is a focal length of a positive lens, in the rear lens group.

A medical otoscope, comprises an otoscope body and an observation apparatus connected to one end of the otoscope body, the other end of the otoscope body having a tapered portion capable of inserting into an ear, the observation apparatus comprising at least one optical lens group arranged along a same optical axis, the optical lens group comprising at least one optical lens capable of moving along the optical axis, central axis of the observation apparatus being coaxial with or deviating from central axis of the otoscope body. The focal length of the medical otoscope can be adjusted by means of arranging two groups of optical lenses movable relative to one another, and the medical otoscope has a simple structure and is convenient for operation.

An imaging optical system includes, in order from an object side, a first lens having negative refractive power, a second lens having positive refractive power, a third lens having positive refractive power, a fourth lens and a fifth lens, with the fourth lens and the fifth lens not cemented, in which a predetermined conditional expressions is satisfied.

An image pickup apparatus includes a flexible substrate, the flexible substrate includes a plurality of functional regions segmented by bending portions, one of the functional regions is an image pickup device mounting region, one of the functional regions is at least two electronic component mounting regions folded at the bending portions, and one of the functional regions is at least one wiring region provided between the adjacent mounting regions of the flexible substrate, the image pickup device mounting region has a largest surface shape among the plurality of functional regions, and the plurality of functional regions decrease in length of each of at least paired opposing sides of each surface shape, in a stepwise manner as a distance from the image pickup device mounting region increases.

An optical component assembly method including shrinking a first end of a heat shrink tube about a first optical component, inserting a loading portion of a loading tube into a second end of the heat shrink tube, radially-inserting a plurality of optical components into a staging portion of the loading tube thereby forming a line of optical components, the staging portion being seamlessly coupled to and integrally-formed with the loading portion, moving the line of optical components from the staging portion into the loading portion, and removing the loading portion from between the line of optical components and the heat shrink tube thereby depositing the line of optical components in the heat shrink tube. The line of optical components is fixed and optically aligned within the heat shrink tube by applying radial pressure, axial pressure and heat to the line of optical components simultaneously.

A lens unit includes a plurality of optical elements stacked, each of the plurality of optical elements including a glass substrate as a base, the glass substrates having a same size in respective cross-sections in a direction orthogonal to an optical path, and the optical elements are lens elements with resin lenses disposed on the respective bases, and each of the plurality of optical elements includes an annular recess portion surrounding the optical path and extending through the glass substrate, and a light shielding wall made of a light shielding material charged in the recess portion.

The present disclosure relates to the field of endoscopy. Specifically, the present disclosure relates to delivery systems and methods for coagulating sites of bleeding within mucosal tissues, and in particular, for eradicating esophageal varices.

A medical imaging system including: imaging circuitry configured to capture an image; a defractive filter array mounted over the sensor circuitry and a separation device configured to adjust the distance between the defractive filter array and the sensor circuitry.

A medical endoscope includes a circuit board, on which an image capture device and a LED bare die are mounted. The LED die is attached to the circuit board and electrically connected to a conductor pattern of the circuit board by conductive members. Next, a sealing member is coated onto the circuit board to embed the LED bare and the conducting members therein. The medical endoscope will have smaller size than the prior arts.

A device for Doppler optical coherence tomography (Doppler OCT), preferably of the human middle ear, is proposed. The device has an endoscope unit for at least partial insertion into the auditory canal. A sound source, a sound receiver, and OCT optics are integrated in the endoscope unit.