摘要:
In order to compensate for the influence of magnetic fields on charged-particle beams, in particular in imaging devices provision is made for a coil constituted by a support plate of substantially constant thickness and by patterns deposited on the support in such a manner as to ensure that the absorption of electromagnetic energy is constant over the entire surface of the coil within a predetermined pass-band.In a first embodiment, the patterns are transparent to the electromagnetic energy of a desired frequency band. In a second embodiment, complementary patterns are employed in order to obtain constant absorption over the entire surface of the coil.
摘要:
A scanning system for optoelectronically recorded signal patterns stored in a plural layer medium consisting of inorganic materials throughout and featuring a dielectric storage layer at the surface which faces an electron beam source. The source beam first searches for a position mark associated with an image frame on the medium in order to establish a precise home position of the beam and associated coordinate axes prior to commencing the scan operation on that medium frame. Then the beam scans a raster on the medium spending a certain dwell time at each resolution element of the raster. Each time a frame is reached, the system is capable of altering the beam current in response to a pre-recorded exposure code in order to achieve the optimal retrieval of all information stored image-wise within said frame. The system then collects electrons emitted from the medium due to the scanning beam in a collector, which incorporates a highly sensitive amplifier, for further processing, with the medium being movable frame by frame as desired.
摘要:
Photoelectric detection device comprising a vacuum chamber provided with a window having a substrate which bears a photocathode on the internal surface of the vacuum chamber is sensitive to incident light radiation between a short wavelength .lambda..sub.1 bottom threshold and a longer wavelength .lambda..sub.2 upper threshold. Electrons emitted by the photocathode are focused, accelerated and deflected by electronic means to deliver signals or an image representative of luminous events projected onto the photocathode. Window is provided with at least one light filter which determines the wavelength range for which the detection device is operational, eliminating wavelengths greater than a wavelength .lambda..sub.f such that .lambda..sub.1
摘要:
In an image pickup tube comprising a glass bulb, a face plate, a target surface, a mesh electrode arranged in opposition to the target surface, and a mesh holder to support the mesh electrode, the mesh electrode having supported with non-uniform tension at various portions thereof by the mesh holder whereby microphonic noise is attenuated rapidly.
摘要:
Television camera tube comprising a tubular envelope of glass drawn on a mandril and having an internal conductive wall coating. A diaphragm having an aperture is supported in the envelope by a supporting surface extending transverse to the longitudinal axis of the envelope. The supporting surface is formed by a substantially stepwise change in the internal transverse dimension of the envelope. The conductive wall coating is interrupted at a distance from the diaphragm. The stepwise change in the internal transverse dimension of the envelope portion taking place in at least a first a step and second step. The first step forms the supporting surface for the diaphragm. The interruption (6) in the conductive wall coating is provided on the second step. If the diaphragm in such a tube is a flat plate and the distance d between the first step and the second step is between 0.4 D and D, where D is the inside diameter of the envelope between the first and the second step, the axial astigmatism.
摘要:
A programmable optical sensor is formed by coupling a proximity focused channel intensifier tube to a silicon target vidicon. The photocathode is gated by a first time programmed voltage and the gain of the microchannel plate is also controlled by a second time programmed voltage. The second voltage is less than 1,000 volts permitting the use of solid state circuitry.
摘要:
A deflection device for the electron beam, in, for example, an image pick-up tube, comprising an annular yoke of a magnetic material, having at least two pairs of diametrically arranged, inwards directed cores which are enveloped by deflection coils. On the inner end of each core there is provided a poleshoe in the form of a ring segment, said poleshoes enclosing a deflection space. In order to ensure that the shape of the generated deflection fields can be accurately and reproducibly defined, each coil is situated, viewed from the deflection space, completely behind the associated poleshoe, the spaces between the poleshoes being bridged by intermediate pieces of a non-magnetic material.
摘要:
An image pickup device includes an image pickup tube, a coil assembly disposed around the image pickup tube, and elastic members disposed on the inner circumferential surface of the coil assembly in the proximity of an extremity at the side of a face plate of the image pickup tube and an extremity at the side of the stem thereof for coaxially fixing the image pickup tube and coil assembly, said elastic members comprising a commercially available O ring of elastic material.
摘要:
A method and apparatus to collating patterns, which is capable of detecting non-overlapping portions of two or more patterns. The apparatus comprises a channel plate having a recovery time response, a phosphor screen for converting secondary electrons emitted by the plate into a scintillation image, and means for controlling the motion of the secondary electrons from the plate toward the phosphor screen. The non-overlapping portions are illuminated on the phosphor screen in a noticeable manner.
摘要:
A method of sealing articles in a vacuum-tight manner by using a sealing body having a circular cross-section and consisting of lead or aluminum or an alloy of one of these metals. A pressure is exerted at the sealing temperature in such a manner that the sealing body undergoes a quick and strong plastic deformation.