Compact holographic sight

A compact sight for small arms comprising:

• a base including at least one connector for mounting the base on the small arm;
• a hologram of a reticle pattern mounted on the base;
• a laser diode light source mounted on the base for illuminating the hologram;
• a power source mounted on the base and operably connected to the light source;
• a brightness adjuster for controlling the brightness of the reticle pattern.

A compact sight for small arms comprising:

• a base including at least one connector for mounting the base on the small arm;
• a hologram of a reticle pattern mounted on the base;
• a laser diode light source mounted on the base for illuminating the hologram;
• a power source mounted on the base and operably connected to the light source;
• an off-axis holographic lens supported in the path of the light beam for collimating the light beam.

A compact sight for small arms comprising:

• a base including at least one connector for mounting the base on the small arm;
• a hologram of a reticle pattern mounted on the base;
• a laser diode light source mounted on the base for illuminating the hologram;
• a power source mounted on the base and operably connected to the light source;
• and
• an achromatizer including a diffraction grating supported in the path of the light beam for reducing shifts in the position of the alignment indicia due to variations in the wavelength of the light beam wherein the diffraction grating is tilted at a sharper angle than the hologram, and wherein the achromatizer further includes at least one prism bonded to the diffraction grating in the path of the light beam between the laser diode and the diffraction grating.

A compact sight for small arms comprising:

• a base including at least one connector for mounting the base on the small arm;
• a hologram of a reticle pattern mounted on the base;
• a laser diode light source mounted on the base for illuminating the hologram;
• a power source mounted on the base and operably connected to the light source;
• a collimator supported in the path of the light beam for collimating the light beam;
• and
• a diffraction grating mounted in the path of the light beam between the laser diode and the hologram such that the collimated beam is incident on the grating at a sharper angle than the output angle of the hologram, thereby expanding the beam size in the direction of diffraction to provide a uniform illumination pattern for the hologram.

A compact sight comprising:

• a hologram of alignment indicia;
• a laser diode for providing linearly polarized light beam for illuminating the hologram;
• collimating means supported in the path of the light beam for collimating the light beam;
• and
• a brightness adjuster for controlling the brightness of the alignment indicia.

A compact sight for small arms comprising:

• a base including means for mounting the base to the small arm;
• a power source;
• a hologram mount secured to the base, the hologram mount including adjustment means for rotating a hologram of alignment indicia mounted thereon about two perpendicular axes in the plane of the hologram;
• the hologram supported on the hologram mount generally perpendicular to the line of sight from the viewer to a target;
• a laser diode connected to the power source and supported on the base for providing a linearly polarized light beam of relatively unstable wavelength for illuminating the hologram, the light beam having a generally elliptical intensity pattern;
• a brightness adjuster for controlling the brightness of the alignment indicia;
• collimating means supported in the path of the light beam for collimating the light beam;
• achromatizing means supported in the path of the light beam for reducing shifts in the position of the alignment indicia due to variations in the wavelength of the light beam emitted by the laser diode;
• and
• circularizing means supported in the path of the light beam for circularizing the light beam to provide a uniform illumination pattern for the hologram.

A compact sight for small arms comprising:

• a base including means for mounting the base to the small arm;
• a power source;
• a hologram mount secured to the base, the hologram mount including adjustment means for changing the elevation and azimuth position of the reticle image;
• a hologram of alignment indicia supported on the hologram mount generally perpendicular to the line of sight from the viewer to the target, the hologram having a spatial frequency of F;
• a laser diode connected to the power source and supported on the base for providing a linearly polarized light beam of a relatively unstable wavelength, .lambda., for illuminating the hologram, the light beam having a generally elliptical intensity pattern;
• a brightness adjuster including,
• a linear polarizer mounted on the base in the path of, and in alignment with, the linearly polarized light beam,
• a liquid crystal device mounted in the path of the light beam between the laser diode and the linear polarizer, and
• a variable control for providing a selected AC voltage to the liquid crystal device to vary the rotation of the plane of the polarized light transmitted through the liquid crystal device as a function of the AC voltage, thereby controlling the orientation of the beam transmitted to the linear polarizer and the brightness of the alignment indicia;
• an aspheric collimating lens mounted in the path of the light beam to collimate the diverging beam;
• at least one diffraction grating bonded to a prism having a refractive index n and mounted in the path of the collimated beam to direct the light to the hologram at a wavelength-dependent angle which compensates for the wavelength-dependent diffraction of the hologram to produce a stable reticle pattern independent of the laser emission wavelength.

A compact sight for small arms comprising:

• a base including means for mounting the base to the small arm;
• a power source;
• a hologram mount secured to the base, the hologram mount including adjustment means for changing the elevation and azimuth position of a reticle image;
• a hologram of alignment indicia supported on the hologram mount generally perpendicular to the line of sight from a viewer aligning the small arm with a target, the hologram having a spatial frequency of F;
• a laser diode connected to the power source and supported on the base for providing a linearly polarized light beam of a relatively unstable wavelength, .lambda., for illuminating the hologram, the light beam having a generally elliptical intensity pattern;
• a brightness adjuster including a control for modulating the output of the laser diode into a pulse train with a frequency greater than 60 Hz and for varying the width of the pulses in the pulse train;
• an aspheric collimating lens mounted in the path of the light beam to collimate the light beam;
• and
• at least one diffraction grating bonded to a prism having a refractive index n and mounted in the path of the light beam to direct the light to the hologram at a wavelength-dependent angle which compensates for the wavelength-dependent diffraction of the hologram to produce a stable reticle pattern independent of the wavelength of the light beam.