The Konica Domirex was a prototype camera from 1963.
Background
It was a 35mm SLR, using an unusual
mirror
A mirror or looking glass is an object that reflects an image. Light that bounces off a mirror will show an image of whatever is in front of it, when focused through the lens of the eye or a camera. Mirrors reverse the direction of the im ...
arrangement to eliminate the need for the mirror to flip up out of the way prior to exposure. It's still an "SLR", although it looks more like a
rangefinder
A rangefinder (also rangefinding telemeter, depending on the context) is a device used to measure distances to remote objects. Originally optical devices used in surveying, they soon found applications in other fields, such as photography an ...
or
viewfinder
In photography, a viewfinder is what the photographer looks through to compose, and, in many cases, to focus the picture. Most viewfinders are separate, and suffer parallax, while the single-lens reflex camera lets the viewfinder use the main ...
camera, b. The reason is that a "
single lens reflex
A single-lens reflex camera (SLR) is a camera that typically uses a mirror and prism system (hence "reflex" from the mirror's reflection) that permits the photographer to view through the lens and see exactly what will be captured. With twin l ...
" camera, by definition, uses a mirror to reflect light that's passed through the single lens into the viewfinder. The advantage of this is that the user sees exactly what the camera is "seeing". The Domirex uses a number of small mirrors to redirect the image to the viewfinder, rather than a single large mirror along with the bulging
pentaprism
A pentaprism is a five-sided reflecting prism used to deviate a beam of light by a constant 90°, even if the entry beam is not at 90° to the prism.
The beam reflects inside the prism ''twice'', allowing the transmission of an image through a r ...
typical of 35mm SLR cameras.
The iris diaphragm and the leaf shutter are mounted behind the rear lens element.
[US Patent 3274912]
''Single-lens Reflex Camera'', filed by Tadashi Kasahara for Konishiroku in 1962 and granted in 1966, a
Espacenet
the patent search facility of the European Patent Office. The patent shows diagrams of the camra, and describes various options for viewfinder focusing.
The system has the disadvantage that focusing must be performed using only a small fraction of the available light.
at JJ'
(text in French; archived at archive.org in 2018).
The Domirex was never put into full production, and apparently only had a fixed, 57mm lens. Screw-on wide-angle and telephoto attachments were also made. The camera existed in two versions, one with a selenium cell and one with a Cds cell.
References
Domirex
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