| 摘要 |
PURPOSE:To separate and detect the presence or absence of the position deviations and angle devications of an optical path by providing two beam splitters which are disposed in parallel, two two-dimensional light spot position detecting elements that receive the branched beams from the beam spliters, and a signal processing part that processes the position signals from both detecting elements. CONSTITUTION:Parallel beam fluxes are partly branched with a beam splitter 1, and the branched light is detected with a two-dimensional light spot position detecting element 2. The light transmitted through the splitter 1 is partly branched with a beam splitter 3 and the branched light is detected with a two- dimensional light spot position detecting element 4. The position signals of the luminous fluxes detected with the elements 3, 4 are applied to a signal processing part 5, by which the presence or absence of the axial deviations of the parallel beam fluxes in their X and Y directions as well as the angle deviations in their horizontal and vertical directions is detected separately. |
