Agfa-gevaert Ag

Theodor Huber

Kurt Borowski

Istvan Cocron

Eduard Wagensonner

Gerhard Egger

Peter Lermann

Wolfgang Ruf

Friedrich Stumpf

August Hell

Bernhard Von Fischern

When the battery voltage is sufficient, and not nearing the point of insufficiency, a light-emitting diode is steadily illuminated. As the battery voltage decreases, the steady component of illumination decreases and also, when the decrease has proceeded to a certain extent, a superimposed pulsating component of illumination is introduced, causing the illuminated LED to begin to flicker, informing the user that the battery voltage is nearing insufficient values. As battery voltage drops further, the steady component of illumination ceases altogether, and the flicker converts to on-off blinking, indicating that the battery voltage is at the verge of an insufficient value. When the battery voltage drops fruther, the LED ceases to be illuminated. During part or all of the flicker phase, and/or during part or all of the blinking phase, the frequency of the pulsating component of illumination progressively increases with decreasing battery voltage, to create an effect of increasing urgency. In addition, or alternatively, at a certain point during pulsating illumination the frequency of the pulsating component is abruptly increased, likewise to create an effect of urgency.

Circuit for indicating the condition of the battery in a photographic

A focussing system of the type which emits radiation from the camera towards the subject, with the radiation reflected from the subject being incident upon a receiving transducer generating an electrical signal from which focus-control information is derived. The emitted radiant-power level is automatically controlled in dependence upon camera-to-subject distance, preferably in dependence upon the power level of the reflected-back radiation incident upon the receiving transducer, even when the focus-control information required for primary system operation is independent of such power level. This makes possible various important improvements, including: automatic lowering of the emitted-power level in close-up contexts, especially where a danger of eye damage might exist; more generally, automatic matching of emitted-power level to the needs of the signal-processing circuitry, permitting signal-processing stages of narrower operative range to be employed on account of the narrower variations in power level of the signal produced by the receiving transducer; and lowered power consumption. Preferably, when a focussing operation is initiated, the emitted power level is initially low or zero and is progressively increased to an automatically selected value without overshoot.

Focussing system with automatic control of emitted radiant power

Pulses of radiation are emitted from the camera to the subject, reflected back to the camera, and incident upon two detectors. The successive pulses produced by the two detectors are applied to respective integrators which trip respective threshold circuits when and if their integral signals reach the threshold value. This inherently reduces detector and other noise present in the processing circuitry. A tolerance-range counter ascertains whether or not, after one threshold circuit is tripped, the other becomes tripped within a predetermined time interval.

Radiation-emissive focussing system with integration of the signals

First and second photodetector signals, whose relative amplitudes depend upon focus error, are integrated to form respective first and second integral signals whose relative rates of change are dependent upon focus error. Each integral signal is applied to two comparators, one whose threshold level is reached first and the other having a threshold level which would be reached second. When one or the other of the two integral signals reaches its first-reached threshold level, this applies a corresponding signal to the data input of a respective flip-flop, and when this faster-changing integral signal then reaches its second-reached threshold level this clocks both such flip-flops. The time elapsing between the faster-changing integral signal reaching its first-reached and then its second-reached threshold level constitutes a tolerance interval, during which the slower-changing integral signal is given an opportunity to try to reach its respective first-reached threshold level. If the slower-changing integral signal reaches its first-reached threshold level within the tolerance interval, then a corresponding signal is applied to the data input of its associated flip-flop as well before the two flip-flops are clocked, with the result that the states of the two flip-flops are the same as if both integral signals had indentical rates of change of value.

Focussing system for cameras

An infrared measuring beam is emitted from the camera towards the subject, and reflected back as a tiny light spot projected, by an optics which transversely shifts in dependence upon exposure-objective subject-distance setting, onto one, the other or both of two infrared photodiodes. The signals from the two photodiodes are transmitted in processed form to two output flip-flops through the intermediary of a single, shared signal-processing stage, employing time-division-multiplexed transmission of the two photodiode signals, to assure that the signal processing of the two photodiode output signals be as identical as possible.

Photographic camera with focussing system which time-multiplexes the

When the battery voltage is sufficient, and not nearing the point of insufficiency, a light-emitting diode is steadily illuminated. As the battery voltage decreases, the steady component of illumination decreases and also, when the decrease has proceeded to a certain extent, a superimposed pulsating component of illumination is introduced, causing the illuminated LED to begin to flicker, informing the user that the battery voltage is nearing insufficient values. As battery voltage drops further, the steady component of illumination ceases altogether, and the flicker converts to on-off blinking, indicating that the battery voltage is at the verge of an insufficient value. When the battery voltage drops further, the LED ceases to be illuminated. During part or all of the flicker phase, and/or during part or all of the blinking phase, the frequency of the pulsating component of illumination progressively increases with decreasing battery voltage, to create an effect of increasing urgency. In addition, or alternatively, at a certain point during pulsating illumination the frequency of the pulsating component is abruptly increased, likewise to create an effect of urgency.

Circuit for indicating the condition of the battery in a _photographic

A motion picture camera wherein the diaphragm is adjusted in automatic response to signals from two outputs of a digital comparator which receives a first set of signals during each revolution of the shutter at a frequency varying as a function of changes of shutter speed and of changes of scene brightness. The comparator further receives a set of reference signals from a digital selector circuit during normal operation of the camera or from a binary counter when the camera is set for making exposures with fade-in, fade-out or lap dissolve. The counter forms part of a program circuit.

Motion picture camera

Normally, the negative-feedback diaphragm control system of the motion-picture camera works off a through-the-lens photosensitive element. However, when an image fadeover is to be effected, the lower than normal-operation aperture size commanded for the diaphragm results in a decrease in the light incident on the through-the-lens photosensitive element creating problems if the diaphragm control system is to continue to respond to scene-light changes during the lower than normal-operation aperture-size situation. Accordingly, the through-the-lens photosensitive element is switched out of the control system, and a second photosensitive element is switched in. The second photosensitive element does not operate through-the-lens, but instead is positioned behind an auxiliary light attenuator the front of which is exposed to ambient scene light. The auxiliary light attenuator is coupled to the diaphragm and diaphragm-adjusting motor. When the second photosensitive element is switched in, also switched in is a corrective unit which redefines what the equilibrium state of the negative-feedback diaphragm control system is to be, to take into account the difference in light incident upon the second as opposed to the first photosensitive element.

Altered negative-feedback diaphragm control during implementation of

A single operating switch replaces the main switch connecting the diaphragm control means to the battery and the release switch activating the film transport. All camera circuits are directly connected to the battery when the main operating switch is closed. An electronic switch is connected in series with the film transport motor and is closed only upon receipt of a control signal. In a first embodiment the control signal is furnished by a timing circuit after a predetermined time interval following the activation of the main operating switch. In a second embodiment the control signal is furnished by a NAND-gate which has a first input which receives a '1' signal while the diaphragm is being adjusted and a second input which receives a '1' signal while the electronic switch is open. The NAND-gate thus furnishes a '1' signal to the electronic switch causing it to be conductive at all times except when the initial adjustment of the diaphragm takes place.

Growing community of inventors

Munich, Germany

Theodor Huber