The endoscope system (10) includes a light source unit (20) that emits correction illumination light to be used for the correction in the correction mode in which the biological information observation mode is corrected and emits white light at least once; a compensation amount calculation unit (76) that calculates a compensation amount of data to be used in the biological information observation mode using correction images obtained using the correction illumination light; a correction unit (77) that corrects the biological information observation mode by compensating for the data using the compensation amount; and a display control unit (66) that displays a white light image, which is obtained by imaging the observation object using the white light, on a display unit in the correction mode.

An image pickup apparatus includes an image forming optical system which includes an aperture stop that determines an axial light beam, and one cemented lens, and an image pickup section which is disposed on an image side of the image forming optical system, and which has a surface which is not flat and is curved to be concave toward the image forming optical system, wherein the cemented lens includes in order from an object side, a first lens having a negative refractive power, a second lens, and a third lens having a positive refractive power.

A signal processing apparatus 6 includes a mode selection unit 6124 that selects any operational mode from among a plurality of operational modes that include a regular operational mode in which a video signal for display is output, and are hierarchically organized in a tree form, the mode selection unit 6124 causing the signal processing apparatus 6 to operate in the selected operational mode. The operational modes include a plurality of lower-level operational modes as lower-level operational modes having a parent-child relation with the regular operational mode. The mode selection unit 6124, after the signal processing apparatus 6 has started up, selects any operational mode from among same-level operational modes for each level from an upper level toward a lower level and, when having selected any of the lower-level operational modes, can select an upper-level operational mode relative to the selected lower-level operational mode on condition that the signal processing apparatus 6 has again started up.

A lens system (1) for a video endoscope comprises, in order from an object side, a cover glass (20), a first lens (40), a second lens (60) and one or more further lenses, wherein all lenses are single lenses. An aperture stop (21) is arranged at the object side of the first or the second lens (40, 60), all lenses on an image side of the aperture stop (21) are aspherical, all lenses are made of glass or of a crystalline material, and at least one lens has a refractive index n approximately equal to or exceeding 1.66. The invention also relates to an endoscope objective, to a video endoscope, and to a method for assembling an endoscope objective.

Apparatuses and methods for an interposer for integration of multiple image sensors are disclosed herein. An example apparatus includes an interposer including laterally spaced first and second windows, and first and second image sensors disposed on the interposer over the first and second windows, respectively. The interposer including conductive conduits formed in or on to provide electrically conductive paths there through with the first and second image sensors coupled to the conductive conduits. The first and second image sensors laterally spaced by a gap, and an active area of the first and second image sensors to receive incident light through the respective first and second windows, where a perspective of the first image is different than a perspective of the second image sensor based at least in part on the gap.

Provided is an endoscope objective optical system including, in order from an object side, a first group having negative refractive power, a second group having positive refractive power, and a third group having positive refractive power. The second group is provided so as to be movable in an optical-axis direction. The following conditional expression is satisfied,
9<f2/fa<16(1)
where f2 is a focal length of the second group, and fa is a focal length of the entire system in the normal observation state.

Provided is an endoscope objective optical system including, in order from an object side, a first group having negative refractive power, a second group having positive refractive power, and a third group having positive refractive power. The second group is provided so as to be movable in an optical-axis direction. The following conditional expression is satisfied,

9<f2/fa<16(1)

where f2 is a focal length of the second group, and fa is a focal length of the entire system in the normal observation state.

An optical unit capable of curbing penetration of moisture into the optical unit is provided. The optical unit includes a plurality of lenses constituting an optical system, a cylindrical first lens frame that holds at least a first lens disposed closest to an object side among the plurality of lenses and has a first screw portion formed thereon, and a cylindrical holding frame on which a second screw portion is formed, wherein the first screw portion and the second screw portion are fitted to each other such that the first lens frame is fixed to the holding frame.

The object lens 21 and the ocular lens 22 are disposed in the lens barrel unit 11 and the relay lens system 23 is disposed therebetween. The image sensor 31 is disposed in the camera unit 12 and the coaxial illumination unit 32 is disposed therearound. The focus position shift member 25 is disposed at the image formation position L1 in the lens barrel unit 11. The light from the coaxial illumination unit 32 is imaged at the image formation position L1 and is shifted to a position L2 by the focus position shift member 25. Since the position L2 positions at a position closer than a focus position, light through the object lens 21 diffuses to illuminate the object 51.

An image pickup unit includes a three-dimensional wiring board, an image sensor and one or more optical lenses and resin. In the resin, a transmittance and a reflectance of light having a wavelength of 380 to 780 nm are equal to or lower than 0.5% and equal to or lower than 5%, respectively, and when a value of a bidirectional reflectance distribution function in a direction in which an azimuth angle from an incident surface is r and a polar angle is r, with a polar angle in an incident direction as i is BRDF (i, r, r), in a case where i is 45 to 75 degrees, r is 60 to 60 degrees, and r is 85 to 85 degrees, the value of the bidirectional reflectance distribution function is equal to or lower than 0.1 of incident light, in which, r0 and ir.