Day and night sighting system

摘要

An integrated day and night sighting system and a laser rangefinder apparatus includes a daylight objective lens having a night light corrector lens mounted adjacent to and coaxially with the daylight objective lens and having an eyepiece lens. An image converter module may be an image intensifier for night light use and is movably supported for movement between a daylight position out of the light path and a night light position in the light path. The image converter is positioned to focus the night light optics thereon and for the eyepiece lens to view the image intensifier screen. A night primary objective mirror is positioned to reflect light from the night objective lens and a night secondary mirror is positioned to receive light from the primary objective mirror and to focus the night light onto the image converter when the image converter is in the night light position. This allows a refractive day sight to be integrated with a reflective night sight. The night light corrector lens are tilted in the rangefinder to compensate for beamsplitter astigmatism to give diffraction limited on-axis performance. The sighting system is incorporated into a laser rangefinder having a laser for transmitting a laser beam and a receiver for receiving the reflected laser beam.