Patent GB-100940-A (GB)
Title: Improvements in the Method of and Apparatus for Transforming Motion into Electrical Waves or Impulses.
Inventor: DIXON THOMAS BULLITT
IPC: H04L13/18
Filed: 1916-02-19
Abstract: 100,940. Dixon, T. B. July 19, 1915, [Con cention date]. Radiometers.-A number of pencils of light or other radiant energy obtained from one or more sources are rendered coincident on a movable reflector by means of lenses and reflectors and after reflection from the movable reflector are rendered coincident, by means of lenses and reflectors on one or more selenium cells or the like placed in the circuit of a receiver such as a telephone receiver or siphon recorder. The light pencils are arranged to have the same rectangular cross-section at the points of incidence on the moveable reflector and cells. The movable mirror may be operated by a telephone transmitter or receiver by the diaphragm of a phonogragh or by the moving- cuil instrument of a cable telegraph system. In the arrangement shown in Fig. 1, a number of light pencils from a source 3 are rendered coincident on a movable mirror by means of condensiug-lenses 4 reflecting prisms 5 and lenses 6; while the reflected pencils 8<a> are rendered coincident on a selenium cell 2 by means of reflecting prisms 7. A reflector 9 or a system of reflecting prisms is placed at the back of the source 3. In a modification the pencils of light are rendered of equal length by placing a system of reflectors behind the prisms 5 and lenses 6. In a further modification the condensing lenses 4 are replaced by two condensing lenses and the lenses 6 by a single lens. In a further modification some of the reflecting prisms 5 are replaced by one or two retracting prisms. In the modification shown in Fig. 12 the movable mirror 1<a> is provided with two reflector surfaces obtaining light from all sides of a single source 3 or from two separate sources. The reflected pencils 8<b> may fall on a single cell 2 or by suitably arranging the reflectors 7<a> upon several cells. In the modification shown in Fig. 21 the light pencils from a source 3 are arranged to be reflected from two movable concave mirrors 1<a> and after refraction at the lens 30 and reflection at the mirrors 7<a> to fall on two tiers of cells 2. The reflected pencils 8<b>, Fig. 21. may be arranged to fall on a single tier of cells by interposing two inclined mirrors between the reflectors 7a and the cells. In a further modification the primary and secondary reflectors are divided into two groups while two condensing lenses are placed between the movable mirror and the secondary reflectors. The condensing-lenses 4, Fig. 30, are held in a frame consisting of slotted members 45, 46 held together by end members 47. The coil 10, Fig. 2, of the recorder consists of two opposing windings placed between magnet poles 11 and each connected to circuit with a selenium cell 2. Normally the coincident light pencils 8<b> fall equally in the cells 2, and the windings of the coil 10 neutralize each other. When, however, the position of the pencils 8<b> is varied the balance is upset. In a modification the normally balanced windings may be primary windings of a transformer the secondarv winding of which is connected to the recorder. In a further modification the adjacent ends of the cells are connected to opposite poles of two batteries, the other ends of the cells being connected to the other poles of the batteries through the recorder. In a further modification the cells constitute the arms of a wheatstone bridge while in the further modification shown in Fig. 28 two recorders are employed, the light pencils 8<b> normally falling between the two cells 2. The Specification as open to inspection under Sect. 91 (3) (a) describes the arrangement of a large mirror divided into separately mounted sections which are harnessed together and to the moving coil. This subject-matter does not appear in the Specification as accepted, but is fully described in Specification 102,264.