Planetarium and point light source for use in same
AssigneeLearning Technologies, Inc.
InventorPhillip M. Sadler
Life of this patent
Estimating the term…
Abstract
Featured is a portable planetarium device suitable for use in projecting clear bright images of stars, planets, and other celestial objects onto a curved viewing surface. The portable planetarium devices of the invention comprise a point light source generators, a light dispersing lens assembly, and an opaque enclosure having transparent domains surrounding the light dispersing lens assembly. Also featured is a portable point light source comprising a light source, a light collection element and a light conducting conduit suitable for use in providing high intensity light with a small cross-sectional area.
Claims17
A planetarium projector comprising:
- a point light source having substantially symmetric light intensity and an apparent cross-section of less than about 2 mm which is capable of generating a beam of high-intensity light having a cone angle θ;
- an enclosure having opaque regions and transparent regions that correspond to locations of individual celestial stars, wherein the enclosure includes an inner surface and an outer surface;
- and
- a light dispersing lens assembly disposed within the enclosure such that the beam of light having a cone angle θ from the point light source enters the light dispersing lens assembly and a beam of light having a cone angle θ′ exits the light dispersing lens assembly wherein θ<θ′ and the beam of light exiting said light dispersing lens assembly fully illuminates the inner surface of said enclosure.
A planetarium projector comprising:
- a point light source having substantially symmetric light intensity and an apparent cross-section of less than about 0.5 mm which is capable of generating a beam of high-intensity beam light having a cone angle θ;
- an elliptical mirror or a dual paraboloid reflector system, wherein the point light source is situated at a first focus of the elliptical mirror or the dual paraboloid reflector system such that a substantial portion of the light generated by the point light source is concentrated at a second focus of the elliptical mirror or the dual paraboloid reflector system;
- an enclosure having opaque regions and transparent regions that correspond to locations of individual celestial stars, wherein the enclosure includes an inner surface and an outer surface;
- a light dispersing lens assembly disposed within the enclosure such that the beam of light having a cone angle e from the point light source enters the light dispersing lens assembly and a beam of light having a cone angle θ exits the light dispersing lens assembly wherein θ<θ′ and the beam of light exiting said light dispersing lens assembly fully illuminates the inner surface of said enclosure;
- and
- a light-conducting conduit which is interposed between the point light source and the light dispersing lens assembly such that a proximal end of the light-conducting conduit is disposed at the second focus of the elliptical mirror or the dual paraboloid reflector system and a distal end of the light-conducting conduit is disposed adjacent to the light dispersing lens assembly such that substantially all of the light from the point light source which enters into the light dispersing lens assembly passes through the light-conducting conduit.
Dependencies are inferred from the claim text.