| 摘要 |
An optical instrument for use in locating indicator lights or the like on a work surface comprises a tubular housing, a lens mounted within the housing and including an inner surface coated with a dichroic material that is capable of reflecting a portion of the light incident thereon, a plate mounted within the housing opposite the lens and having a central aperture, a transparent substrate disposed within the housing intermediate the lens and the plate, the substrate including a first surface disposed in a facing relationship to the dichroic material, and a reticle formed on the first surface and comprised of a material capable of reflecting light, the reticle including a reference pattern and a plurality of contours each representing an iso-response time for an average viewer to respond to a light of a preselected color, whereby when the aperture is placed in front of the eye of a viewer ambient light passing through the lens and striking the reticle is reflected from the reticle against the coating which in turn reflects a portion of the light through the substrate and the aperture into the eye, and whereby the reference pattern and the contours appear to be projected upon the work surface so as to permit the viewer to locate indicator lights on the work surface such that the lights are capable of being observed and hence responded to within a desired response time.
|
