| 摘要 |
The device produces in a given central working plane a flux having an aperture angle of a predetermined value, in which the intensity of the projected radiation varies from its maximum to a value of about one half of the latter. The device comprises a source of radiation (4) and a reflector (5, 6). …<??>The reflector comprises:… - either a front part consisting of a mirror of the conoid or pyramidal type having at least two opposite reflecting surfaces (5, 6) which are dimensioned and positioned in space in order that the geometric characteristics of their profile in a mirror section, by a plane of symmetry, substantially satisfy a given system of dimensioning relationships,… - or at least one fraction of its rear part (31) reflecting and having at least one meridional section in the form of an arc of a circle axially centred in front of the source in order that the reflected radiation has a point of convergence situated in front of the outermost part of the source and from which this reflected radiation extends with a substantially uniform distribution over an angle which is furthermore such that the total flux finally obtained is spread over the so-called aperture angle of the device with the desired value,… - or both these arrangements at the same time. …<IMAGE>… |
