DE1021711B - Photographic or cinematographic recording device with photocell and device for exposure adjustment - Google Patents

Description

Patent 938,822 relates to a photographic or cinematographic recorder having a Objective composed of lenses or lens elements as well as with a photocell for exposure measurement and means for transmitting the measured value Brightness value on a device with which the exposure of the receiving layer by change the exposure time and / or the aperture can be influenced. The new thing here is that the photocell is ring-shaped and between two lenses or lens elements of the objective is arranged.

A significant improvement - especially in terms of manufacturing technology Art - can be achieved with a lens according to the main patent, if according to present invention, the ring-shaped photocell as a photoelectric layer directly on one of the Lens surfaces of the lens is applied.

It has already been proposed in other photographic recording apparatus, a photoelectric Apply the layer directly to the folding mirror of a single lens reflex camera. On the other hand, he has Subject matter of the invention has the advantage of being usable with cameras of any type.

The drawing schematically illustrates an embodiment of the subject matter of the invention, where - according to the designations in the main patent - α denotes the camera housing, b the shutter and c the taking lens, the latter consisting of the front lens 1, a middle negative lens 2 and a cemented rear member 3. d is the adjusting for receiving aperture and e of which are coupled together for the additional diaphragm /.

The photocell g is ring-shaped and, according to the invention, is applied directly to one of the lens surfaces, for example to the rear surface of the front element 1 of the taking lens c. This front member 1 is expediently enlarged by the amount of the covering surface of the photoelectrystic layer g , so that in this way the original aperture ratio of the system is retained.

In the arrangement and formation of the photoelectric layer g shown in the example, which is shown in plan view in FIG. 2, the additional diaphragm / is attached in front of the front element 1 of the lens element; but if the photoelectric layer is applied to a surface of the following diffusing element 2, then the diaphragm / should be provided between the front and the following second element of the system.

Photographic or

cinematographic recording device

with photocell and device

for exposure adjustment

Addendum to patent 938 822

Applicant:

Jos. Schneider & Co. Optical Works,
Bad Kreuznach (RhId.)

Dr. Karl Johann Weiss, Bad Kreuznach (RhId.),
has been named as the inventor

In accordance with the embodiment according to the main patent, the photocell g is connected to the display instrument i (capillary electric motor or galvanometer) arranged on the camera housing by means of lead wires h. / is a rotatable ring with a recess / which is to be brought into line with a pointer of the indicating instrument. In the example chosen, this rotation is transmitted by a shaft / to an adjusting ring k for the shutter speed.

Claims (1)

Claim Photographic or cinematographic recording device with an objective composed of lenses or lens elements and with a photocell for exposure measurement and means for transmitting the measured brightness value to a device with which the exposure of the recording layer can be influenced by changing the exposure time and / or the aperture, according to the patent 938 822, characterized in that the ring-shaped photocell is applied as a photoelectric layer (g) directly to one of the lens surfaces of the objective (c). Considered publications: French patent specification No. 928 745. 1 sheet of drawings 709 845/296 12.5?