Abstract: An optical element disposed behind a main mirror and inclined relative to the optical axis is arranged at a position to correct aberration in the luminous flux generated by transmission through the main mirror.

Abstract: In an optical unit such as AF sensor used in a camera, a sensor module is directly fixed on a flexible printed circuit substrate in a manner so that an array of photo-sensing devices formed on the sensor chip is directly connected to conductive patterns on the flexible printed circuit substrate. The printed circuit substrate with the sensor module is held by a sensor holder, and the sensor holder is fixed on an exit opening of a base member of the optical unit in a manner so that the photo-sensing surface of the sensor chip is perpendicular to an optical axis of optical elements such as lenses held on the base member.

Abstract: The AF sensor module primarily comprises condenser lens 16, mirror 17, aperture mask 18, separator lens 19 and CCD 20. Separator lens 19 is located such that its lengthwise center line M may be parallel to the lengthwise center line N of CCD 20 while it is inclined by micro-angle &dgr; with center line M as the rotational axis. By arranging the lens surface of separator lens 19 and the image pickup surface of CCD 20 such that they are non-parallel to each other, reflected light L1 existing due to the reflection of light between separator lens 19 and CCD 20 is prevented from striking CCD 20 once again so that a reduction in the accuracy of focus detection caused by said reflected light may be prevented.

Abstract: The AF sensor module primarily comprises condenser lens 16, mirror 17, aperture mask 18, separator lens 19 and CCD 20. Separator lens 19 is located such that its lengthwise center line M may be parallel to the lengthwise center line N of CCD 20 while it is inclined by micro-angle &dgr; with center line M as the rotational axis. By arranging the lens surface of separator lens 19 and the image pickup surface of CCD 20 such that they are non-parallel to each other, reflected light L1 existing due to the reflection of light between separator lens 19 and CCD 20 is prevented from striking CCD 20 once again so that a reduction in the accuracy of focus detection caused by said reflected light may be prevented.

Abstract: An optical element disposed behind a main mirror and inclined relative to the optical axis is arranged at a position to correct aberration in the luminous flux generated by transmission through the main mirror.

Abstract: A focusing lens for adjusting the dioptric power in accordance with the user's dioptric power is provided in each of right and left lens barrels. When a main switch dial is set at a normal position, a microcomputer sets the focusing lens at a dioptric power of 0 by controlling a motor so that the focusing lens moves to a position corresponding to a dioptric power of 0.

Abstract: A binocular comprising a housing and a pair of first and second optical systems positioned on each side of a central line. Each optical system includes an object lens and ocular lens arranged at a front part and at a rear part of the housing respectively. Further, a light admitting window is placed on the central line between the first and second optical systems for admitting light from an object. A detection module, provided independently of the first and second optical systems is used to output electrical signals which represent the distance to the object. The detection module may include an optical path deflecting means for z-shapely deflecting the light from the light admitting window and for directing the light to a sensor. The binocular is compact and has a hand grip that is designed in order to be holdable and focusable by the use of a single hand.