Abstract: The invention relates to a method of and an apparatus for recording image information in panoramic X-ray photography. The total information contained in a beam of X-rays penetrated through an object is recorded on a memory disc, whose configuration is substantially the same as that of an object to be imaged, such as a dental arch, said memory disc being kept stationary during the filming relative to the object to be imaged. The memory disc is used for producing or presenting layerwise reproduced images of desired layers. The preparation of reproduced images from the memory disc can be performed on a principle corresponding to conventional panoramic tomography with the exception that the object to be imaged is a memory disc.

Abstract: The invention relates to a method of photographing a desired object with a panoramic X-ray apparatus fitted with automatic exposure, comprising an X-ray generator (4, 5), an X-ray tube (5) and a film (7) with its holder. In the method, the detection of a cone of rays (9) penetrated through an object is effected before the actual filming is started and, after the detection, the filming is effected by using a cone of rays (6), directed so as to bypass a detector (1).

Abstract: The invention relates to a power supply circuit for an X-ray tube for converting direct current to high-frequency pulses and including at least two transistors (8, 9) whose collector-emitter circuits are controlled by means of a pulse-width modulator (5) through base control transformers (12) in a manner that transistors (8, 9) operate in push-pull fashion, one terminal (+) of a direct-current source being connected to the collector-emitter circuit of transistors (8, 9). The collector-emitter circuit of each transistor (8, 9) is separately connected through its own transformer (23, 23a) to said one terminal (+) of a direct-current source in a manner that the primary windings (24, 24a) of transformers (23, 23a) serve as ballasts limiting the current passing through transistors (8, 9) and the secondary windings (25, 25a) is connected in series with diodes (26) between the terminals terminals (+ and -) of a direct-current source.