The present invention relates to a process for the production of the profile of reflective elements of a light as well as the lights obtained by this process, the light comprising at least two cylindrical reflective elements (5, 5'). This process is characterized in that it comprises the steps consisting of: defining the position of one end (R.sub.o) of the profile of each reflective element (5, 5') defining an illumination function E(.theta.) corresponding to a desired illumination curve, connected to a luminance function L(.theta.) by the formula: if said end (Ro) of the profile of the reflective element (5, 5') is the downstream end of this latter, and an illumination function: if said end (Ro) is the upstream end of said profile determining, from said end (Ro), the coordinates of each of the points (R) of said profile of each reflective element (5, 5') satisfying the differential equation: in which the function p(.theta.) is equal to .rho.r.multidot.sin(.phi.-.theta.) and the value of the angle .alpha. is equal to (.phi.-.theta.)/r.

Method and apparatus for generating compound shapes in optical surfaces needed to accomodate variable magnification, off-axis projection, reflection from diverse surfaces, reflector relay, intensity pattern requirements and other complex optical transform functions. The present invention permits the realization of mirrors of which provide a variable magnification. The surface generation capabilities permit controlled magnification changes that nevertheless are still image forming and typically avoid the human eye focussing difficulties normally associated with variable magnification mirrors. The present invention includes a computer driven, reflector design system which permits the designer to see the field of view, ray tracings, reflected beam intensity pattern and other data pertinent to a variable magnification mirror from entered mirror specifications. The effect of changes in specifications can be rapidly determined and a final design achieved through one or more such reiterations. The system further determines machine tool motional controls for grinding a surface corresponding to the entered mirror specifications. The capability of the invention in producing irregular optical shapes for these applications is utilized for the production of mirrors that accomplish complex focussing functions for use in off-axis projection mirrors, relay mirrors, and headlamp reflector mirrors. According to the invention, optical systems capable of accomplishing such complex focussing can be realized with a single reflector.

A three-dimensional reflector for object attitude detection responds to illumination from a radiating source to produce a discrete array of light points aligned along a locus on the reflector. The array is characteristic of the reflector position with respect to the radiating source. The reflector has a corrugated surface formed with plural, parallel and spatially periodic, adjacent undulations, each having a crest and a trough. The undulations are arranged such that the locus runs through the reflector center of symmetry and the foot point of a perpendicular dropped by a detector for the array onto the surface. The foot point is a determinate point of the locus.

An electronic strobe light which can either be built into or detachably connected with a photographic camera to provide a preferred illumination distribution over the field of view of the camera in order to maximize flash range and improve the quality of illumination for flash pictures. The strobe light includes a reflector that is bilaterally symmetric about the horizontal having a shape represented by a 6th order polynomial and a strobe tube which has its center offset with respect to the plane of symmetry of the reflector. This arrangement provides a vertically asymmetric distribution in the intensity of illumination over the picture area with higher intensities occurring at the central upper part of the picture area. Side-to-side illumination intensity is generally symmetric about the vertical and is controlled by a cylindrical Fresnel lens.

A reflector having a cross-sectional shape in the form of a 7th order polynomial which, when used with an artificial source of illumination of predetermined geometry, projects a beam of illumination having uniform intensity within a given solid angle. The polynomial shape is especially selected to provide a reflected, defocused source image, whose size increases with increasing angular divergence of light rays within the beam to compensate for natural losses in illumination which would otherwise occur as a function of angular divergence of light rays from the source when used without the reflector.