Abstract:
An X-ray examination apparatus is arranged to convert an X-ray image of an object into an optical image, and to derive an image signal from the optical image by means of an image pick-up apparatus. The image pick-up apparatus includes a controllable amplifier. The X-ray examination apparatus includes an exposure control system with a photosensor for measuring the brightness of the optical image. The exposure control system adjusts the controllable amplifier on the basis of the photosensor signal, representing the brightness of the optical image, and a correction number. The correction number is derived from the image signal.
Abstract:
A condensed single block PAL plus PLA architecture utilizing a rectangular shape is shown. By interleaving the ORterms of the PLA array with the Pterms of the PAL array, is significant amount of die space is saved when incorporating the circuit with silicon. The decode routing required is now simplified and the propagation delay skews through the array are also reduced.
Abstract translation:示出了使用矩形形状的压缩单块PAL plus PLA架构。 通过将PLA阵列的ORterms与PAL阵列的Pterms进行交织,当将电路与硅结合时,可以节省大量的管芯空间。 所需的解码路由现在被简化,并且通过阵列的传播延迟偏移也减少。
Abstract:
The invention relates to a radiation-emitting semiconductor diode, in particular a laser (amplifier) diode, of the buried hetero type which comprises at least one separate confinement layer (4) lying between the active layer (2) and one of the InP cladding layers (1, 3). The active region (2A) has an emission wavelength above 1 mu m and forms part, as do the separate confinement layer (4) and the InP cladding layers (1, 3), of the strip-shaped region (30) which is surrounded by a current-blocking third cladding layer (5) of InP. A disadvantage of the known diode is that its starting current rises comparatively strongly in time, so that the useful life of the diode is limited and indeed too short. In a diode according to the invention, the separate confinement layer (4) comprises an aluminum-containing semiconductor material with at most 30 % aluminum, and preferably at most 20 % aluminum, or an aluminum-free semiconductor material. The short life of the known diode was caused by the presence of oxygen-containing material on the lateral sides of the separate confinement layer (4) adjoining the third cladding layer (5). The degradation is related to the aluminum content of the separate confinement layer (4). Preferably, the separate confinement layer (4) comprises AlGaInAs or GaInAsP. The bandgap and refractive index of the separate confinement layer may have flat, stepped, or gradual profiles. The invention also relates to a method of manufacturing a diode according to the invention.
Abstract:
The irradiation device has a concave reflector (1) and a pair of spaced holders (10) for mechanically holding an elongate electric radiation source (30). The holders (10) have a rigid base (11) and a rigid first wall (12) rigidly connected thereto and a second wall (12). The second wall (12) has a resilient element (14) having an end portion (15) which is directed to the base (11) as well as to the first wall (12) at an acute angle. The element (14) is able to urge a cap (31) of a double-ended capped radiation source (30) towards the base (11) and the first wall (12) so as to hold that source (30) in an aligned position with respect to the reflector (1).
Abstract:
Floor-type vacuum cleaner with a movable housing (1) in which a suction unit (7) is present. The suction unit (7) can be coupled to a suction mouth (21) via a suction channel (23) which comprises a tubular channel (31), a coupling piece (27) with handle (29), a flexible hose (25), and a dust chamber (41). According to the invention, the dust chamber (41) is accommodated in the coupling piece (27). This provides a compact and light-weight housing (1), while the dust chamber (41) is readily and easily accessible to a user of the floor-type vacuum cleaner. In a special embodiment of the floor-type vacuum cleaner, the dust chamber (41) is a bush-shaped chamber which is detachably provided in the coupling piece (27). The dust chamber (41) is provided with a circular-cylindrical permanent dust filter (79) which is rotatable in the dust chamber (41) so as to cooperate with a scraper (89).
Abstract:
The invention relates to the coding of digital information signal blocks comprising representation symbols, such as sampled values, by means of an adaptive variable-length coding, such as Huffman coding. The JPEG Standard also utilizes adaptive Huffman coding, but the coding in accordance with this standard is inefficient when a comparatively large number of Huffman coding tables are to be transmitted. According to the invention, in the case of a small number of representation symbols per information signal block, the probabilities of occurrence of each of the representation symbols are transmitted together with the variable-length-coded representation symbols, a similar (de)coding table being generated both in the encoder and in the decoder on the basis of said probabilities. In the case of a large number of representation symbols per information signal block, information about the number of code words of each length and/or the maximum code length in each series of variable-length-coded representation symbols is added to this series. By means of this information, the decoder can unambiguously generate a coding table. The invention provides a substantial reduction of the number of bits required for specifying the Huffman code tables.
Abstract:
A plasma-addressed electro-optical display device comprising a layer of electro-optical material (42), data electrodes (18) coupled to the electro-optical layer (42) to receive data voltages for activating portions of the electro-optical layer (42), and a plurality of plasma channels (20) extending generally transverse to the data electrodes (18) for selectively switching on said electro-optical portions. The plasma channels (20) each comprise spaced elongated cathode (30) and anode (31) electrodes and an ionizable gas filling (44). The cathode (30) and anode (31) electrodes are arranged in groups to reduce the number of drivers (28) required to drive the cathode (30) and anode (31) electrodes. To further reduce the total number of drivers of a PALC display device which has more pixels per row than rows, the plasma channels (20) are interchanged with the data electrodes (18). The plasma channels (20) now extending in the column direction and the data electrodes (18) extending in the row direction. The video signal (V) to be displayed has to be converted into data signals supplied to the data electrodes (18) in a column wise way instead of in a row wise way.
Abstract:
A dictation apparatus is disclosed (1) for storing a speech signal in memory means (15, 20), the device comprising data compression means (30) for data compressing the speech signal into a data compressed speech signal and storing means for storing the data compressed speech signal in the memory means. The data compression means (30) are adapted to carry out a data compression step on the speech signal in one of at least two different data compression modes, the at least two different data compression modes resulting in different data compression ratios when applied to the same speech signal, the said at least two different data compression modes being selectable by a user. The data compression means (30) are further adapted to create data files (Bi) comprising portions of the data compressed speech signal, the data files comprising a header portion (HDR), the data compression means being also adapted to generate an identifier signal identifying the data compression mode selected and being adapted to store said identifier signal in said header portion. For realizing an insert, control means are present, which is selectively operable by a user for providing an insert signal and an end of insert signal. In response to the occurrence of each insert signal a block of at least two and at most three pointing vectors is generated. The block of pointing vectors comprises a first address signal corresponding to the address generated by address generator means upon the occurrence of the insert signal and a second address signal corresponding to a beginning address of an available portion of said addressable memory for storing a dictation insert.
Abstract:
An imaging system with at least one reflective surface for forming an image by means of ultraviolet radiation, the reflective surface being provided with a correction layer which is transparent to the wavelength of the radiation used. This layer compensates for phase differences caused by deviations of form of the reflective surfaces. The correction layer has a refractive index which differs only slightly from 1, so that the requirements imposed as regards the precision of the surface of the transparent layer are significantly less severe than for the reflective layer.
Abstract:
A reference voltage source comprises a first current branch (16, 36) and a second current branch (30, 34, 12). The voltage on a first terminal (6) in the first current branch (15, 36) is one junction voltage higher than the voltage on a second terminal (8) in the second current branch (30, 34, 12) owing to the presence of a transistor (80). The ratio between the current I1 through the first current branch (16, 36) and the current I2 through the second current branch (30, 34, 12) is thus determined by two non-linear characteristics having opposite temperature coefficients. A reference voltage (Vz) with a small temperature coefficient and with a value which can be chosen freely can be generated by an appropriate choice of the resistance values for the resistors (58, 30, 16, 12) and by scaling the emitter areas of the transistors (34, 36, 70, 80).