Abstract: An electrolyte-based battery cell, having a positive electrode active material layer formed adjacent to a positive electrode collector, a negative electrode active material layer formed adjacent to a negative electrode collector, a separator which has surfaces facing respective surfaces of said active material layers, an electrolyte kept within the separator, the active material layers and there between, and a conductivity measuring means for measuring an electric conductivity of the electrolyte. Also disclosed are a system, and method, for determining the state of charge of an electrolyte-based battery.

Abstract: When a trigger lever is depressed, both a focus adjuster ring and a control disk commence to rotate in unison, driven by a spring mechanism. Position-sensing switches receive signals indicating which subject-distance setting the focus adjuster ring should be arrested at, and furthermore are opened and closed by the control disk during movement of the latter. When the focus adjuster ring reaches the required subject distance setting, it is arrested and kept arrested, thereby completing an automatic focussing operation, but the control disk continues to turn on to its end position, at which it causes the shutter mechanism of the camera to open and furthermore the exposure-timing circuit of the camera to initiation a scene-light-dependent exposure-timing operation.

Abstract: A digital circuit is described for controlling functions of a camera wherein the circuit is powered by a potential source which is connected to the circuit through a relay actuated switch. The circuit employs a plurality of D-flip flops to regulate functions such as film transport and opening and closing of the camera shutter as a function of the light intensity of the scene being photographed. A reset signal generator is used to provide stable and reliable control over the starting condition of the flip flops and render the circuit insensitive to voltage transients as may occur from contact bounce effects at the relay actuated switch. The reset signal generator employs an inverter delay chain to provide like reset pulses when such contact bounce occurs. Various control features are described.

Abstract: A distance measuring system generates an in-range signal when an object is located within a range of focus or a zone of protection, as the case may be. The system utilizes a single infrared transmitter and two receivers in order to determine the position of the object by triangulation.

Abstract: A photographic still or motion-picture camera has a viewfinder and a manually moved focus adjuster, such as a focussing ring. When the user peers into the viewfinder, there is a visible indication of the direction in which the focus adjuster should be manually moved to reduce the state-of-focus error, for example two curved illuminated errors, one pointing clockwise and the other counterclockwise, only one of which lights up to indicate the direction in which the focussing ring should be manually turned. When the state-of-focus error has been reduced to zero or a minimum, this is likewise indicated, for example because neither curved arrow is illuminated. To control the activation of the indicating elements, use can be made of components of a conventional completely automatic focussing system, but minus the adjusting motor of such system and minus superfluous motor-energization control circuitry.

Abstract: A digital control circuit for use in automatic-focus cameras is disclosed, which is suitable for use in self-focusing systems which determine focus by means of triangulation. The system corrects for motor oscillation about a state of proper focus, defocusing caused by inertia, and for an inability to evaluate proper state of focus caused by large distances between the camera and a subject.

Abstract: When a trigger lever is depressed, both a focus adjuster ring and a control disk commence to rotate in unison, driven by a spring mechanism. Position-sensing switches receive signals indicating which subject-distance setting the focus adjuster ring should be arrested at, and furthermore are opened and closed by the control disk during movement of the latter. When the focus adjuster ring reaches the required subject distance setting, it is arrested and kept arrested, thereby completing an automatic focussing operation, but the control disk continues to turn on to its end position, at which it causes the shutter mechanism of the camera to open and furthermore the exposure-timing circuit of the camera to initiation a scene-light-dependent exposure-timing operation.

Abstract: 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.

Abstract: A digital control circuit for use in automatic-focus cameras is disclosed, which is suitable for use in self-focusing systems which determine focus by means of triangulation. The system corrects for motor oscillation about a state of proper focus, defocusing caused by inertia, and for an inability to evaluate proper state of focus caused by large distances between the camera and a subject.

Abstract: At the start of each focussing operation, the camera objective is at a first extreme subject-distance setting and is moved in a first direction therefrom towards the second extreme subject-distance setting. A focus-evaluating circuit comprises first and second photodetectors located to receive light from the subject and a comparing circuit which compares the light incident on the photodetectors and in dependence upon the present subject-distance setting generates first and second signals respectively indicating that the subject-distance setting should be changed in the first direction or in the opposite second direction, such circuit having bidirectional character and furthermore establishing a tolerance range of acceptable distance-setting error within which both the first and second signals are generated. During the unidirectional change of subject-distance setting, the appearance of the first signal leads to generation of a stop signal commanding that the progressive change of distance setting be stopped.

Abstract: A first pulse train whose pulse repetition frequency varies in dependence upon scene light, and a second pulse train whose pulse repetition frequency does not vary in dependence upon scene light, are counted by digital counting circuitry, and a terminate-exposure signal is produced when the digital counting circuitry reaches a predetermined count. The second pulse train serves to establish an upper permissible limit for the duration of the exposure to be performed.

Abstract: 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.

Abstract: 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.

Abstract: A camera includes a viewfinder, an objective and a manually operated focus adjuster. An optical system located in the path of incoming image light splits the incoming image light beam into two component beams projected into respective first and second focal planes. First and second planar arrays of photosensitive elements are located in respective first and second photodetector planes. When the objective is correctly focussed and then defocussed in a first direction, the sharpness of the image on the first array increases and that on the other decreases; if the objective is defocussed in the opposite direction, the opposite occurs. A comparator has two outputs, connected to the elements of the first and second arrays via respective first and second circuit branches. Each circuit branch includes at least one subtractor producing an absolute-value output signal independent of the polarity of the difference between the input signals applied thereto.

Abstract: A first photodetector arrangement comprises three adjoining photodetectors, and a second comprises six. First and second optics, and the two photodetector arrangements, are located immovable on the camera, and the optics project onto the first arrangement an image of a subject which is to form the basis of a subject-distance measurement, without shift between image and photodetectors of the first arrangement so long as the subject-distance is within one of the ranges the system is to furnish; whereas the image projected onto the second photodetector arrangement shifts relative thereto in dependence upon the distance to the subject. The six photodetectors of the second arrangement are subdivided, for signal-processing purposes, into four successive groups, respectively comprised of the first, second and third photodetector, the second, third and fourth, the third, fourth and fifth, etc.

Abstract: A focussing system emits an infrared light beam towards the subject, the reflected beam passing through an infrared filter and being projected by a spot optics as a small spot onto a pair of photosensitive elements. The spot optics shifts in a plane normal to the camera's optical axis in dependence upon rotation of the camera's focussing ring, to vary the distribution of the reflected beam onto the two elements, the distribution being equal between them when the state of focus is correct. A circuit derives, from the output signals of the two photosensitive elements, a state-of-focus signal used to automatically focus or else to indicate to the user the direction in which he should manually adjust focus. When focussing is finished, the photosensitive elements are disconnected from the focussing circuitry and connected to the camera's exposure-control circuitry, to thereby serve a dual function. The infrared filter moves out of the light path of the photosensitive elements.

Abstract: 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.

Abstract: A semiconductor switch connected in the motor current path is controlled by a clocked flip-flop having a switch-ON and a switch-OFF state, capable of changing states only in response to a clock pulse. RPM is selected by establishing the initial count on a downwards counter having a carryover output at which a carryover signal appears when zero count is reached. A first higher-frequency pulse train is counted by the counter. A second lower-frequency train of set pulses has a repetition frequency dependent upon motor speed. The leading end of each set pulse starts the counter counting. An unclocked flip-flop responds to the carryover signal by assuming a motor-speed-too-low state. The clocked flip-flop when clocked responds to the state of the unclocked flip-flop. The trailing flank of the set pulse clocks the clocked flip-flop so that the latter can respond to the state of the unclocked flip-flop and slightly thereafter sets the unclocked flip-flop to the motor-speed-too-high state.

Abstract: A photographic camera has an exposure objective and a focus adjuster device for changing the subject-distance setting of the exposure objective, as well as a transducer generating actual-setting signals dependent upon the setting of the focus adjuster device. An evaluating circuit, operative for ascertaining camera-to-subject distance on one basis or another, produces digital required-setting signals, expressed using a first encoding scheme, whereas the actual-setting signals generated by the aforementioned transducer are expressed using a different, second encoding scheme. The actual-setting signals are applied to the first input of a comparator stage, whose second input receives a transformed version of the required-setting signals, transformed from the first to the second encoding scheme, i.e.

Abstract: 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.