Abstract: The purpose of the present invention is to provide a space ring, a lens system, a method for manufacturing a space ring, and a method for assembling a lens system capable of maintaining a distance between centers of lenses with high accuracy, while easily assembling the lens system without using special equipment. A space ring configured in an annular shape or a rectangular frame shape, wherein at least one main surface 1a is having an inverted shape of a shape of a periphery side of a lens surface 2a of a lens 2 arranged at one side, and a positioning of the lens 2 is performed by surface contacting the one main surface 1a to the periphery side of the lens surface 2a of the lens 2.

Abstract: An image processing apparatus includes a calculation unit configured to calculate a parameter indicating a degree of change of a difference value between signal values of pixel signals of different pixels in an OPB region of an imaging element, and an estimation unit configured to estimate a reference value of a black level which is used for correcting a black level of a signal value of a pixel signal in an effective pixel region of the imaging element, by using a model of the parameter that is calculated by the calculation unit.

Abstract: A device for guiding goods to be fed between a first floor and a second floor over a gap formed between the first and second floors, the device includes: a first plate member to be placed on the first floor; a second plate member to be placed on the second floor, at least one of the first and second plate members having a hook portion engageable with a groove; and a hinge connecting the first plate member and the second plate member, the hinge protruding downwardly from the surfaces of the first and second plate member, the hinge having a size adapted to the gap such that when the device placed between the first and second floors, the hinge can be accommodated within the gap, and engagement of the hinge with the gap and the hook portion provides a stable guide surface for feeding the goods.

Abstract: A combined display and viewing system includes a display panel (6) and an optical subsystem (7,8) having at least one optical element (7) with a rear surface (7) which reflects the displayed information towards the eyes (E) of a user, wherein the focal length (f) of the subsystem satisfies the condition:-0.0005.ltoreq.(1/f)<0.0005 mm.sup.-1.