Hybrid lens system for projectors
A lens system includes an aperture stop, a first lens disposed on a first side of the aperture stop, a second lens disposed on the first side of the aperture stop, a third lens disposed on a second side of the aperture stop, and a fourth lens. The first lens is manufactured from glass. The second lens, the third lens, and the fourth lens are manufactured from thermoplastic. The fourth lens includes a first surface oriented towards the aperture stop and a second surface oriented away from the aperture stop. The first surface is refractive and diffractive to light passing through the lens system.
1 . A projector device comprising:
a camera;
a time of flight sensor;
a light source;
a digital light processor (DLP) including a digital micromirror device (DMD);
a light coupling prism disposed adjacent to the DLP;
a first lens disposed adjacent to the light coupling prism;
a second lens disposed adjacent to the first lens;
an aperture stop;
a third lens disposed adjacent to a first side of the aperture stop, the third lens including:
a first surface oriented towards the aperture stop, the first surface being both refractive and diffractive to light; and
a second surface towards the second lens;
a fourth lens disposed adjacent to a second side of the aperture stop, the fourth lens being manufactured from a first material; and
a fifth lens disposed adjacent to the fourth lens, the fifth lens being manufactured from a second material that is different than the first material.
2 . The projector device of claim 1 , wherein:
the first material comprises a thermoplastic; and
the second material comprises glass.
3 . The projector device of claim 1 , wherein the fourth lens comprises a doublet lens that is translatable to adjust a zoom associated with the projector device.
4 . The projector device of claim 1 , further comprising:
a sixth lens disposed between the second lens and the third lens;
a seventh lens disposed between the sixth lens and the third lens; and
an eighth lens disposed between the fourth lens and the fifth lens.
5 . The projector device of claim 4 , wherein:
the first lens, the second lens, the third lens, the sixth lens, the seventh lens, and the eighth lens are manufactured from a thermoplastic; and
the fifth lens is manufactured from glass.
6 . The projector device of claim 5 , wherein at least one of the first lens, the second lens, the third lens, the sixth lens, the seventh lens, or the eighth lens includes an aspheric surface.
7 . A projector device comprising:
a camera;
a light source;
a digital micromirror device; and
a lens system positioned and arranged to receive light from the light source via the digital micromirror device, the lens system including:
an aperture stop,
a first lens disposed on a first side of the aperture stop, the first lens being manufactured from glass,
a second lens disposed on the first side of the aperture stop, the second lens being manufactured from thermoplastic,
a third lens disposed on a second side of the aperture stop, the third lens being manufactured from thermoplastic, and
a fourth lens being manufactured from thermoplastic, the fourth lens having:
a first surface oriented towards the aperture stop, the first surface being refractive and diffractive to light passing through the lens system, and
a second surface oriented away from the aperture stop.
8 . The projector device of claim 7 , wherein the fourth lens is disposed on the first side of the aperture stop.
9 . The projector device of claim 7 , wherein:
the second lens, the third lens, and the fourth lens are singlet lenses; and
the first lens is a doublet lens.
10 . The projector device of claim 9 , wherein at least one of the second lens, the third lens, or the fourth lens includes an aspheric surface.
11 . The projector device of claim 7 , further comprising a fifth lens disposed on the second side of the aperture stop, the fifth lens being manufactured from thermoplastic, wherein:
the fourth lens is disposed on the second side of the aperture stop; and
the fifth lens is disposed between the fourth lens and the third lens.
12 . The projector device of claim 11 , wherein:
the first lens comprises a doublet lens including a biconvex lens and a negative meniscus lens;
the second lens comprises a positive meniscus lens;
the third lens comprises a biconvex lens;
the fourth lens comprises a positive meniscus lens; and
the fifth lens comprises a biconcave lens.
13 . The projector device of claim 7 , wherein the fourth lens is disposed on the second side of the aperture stop, further comprising at least one of:
a fifth lens disposed on the first side of the aperture stop, the fifth lens being manufactured from thermoplastic;
a sixth lens disposed on the second side of the aperture stop, the sixth lens being manufactured from thermoplastic;
a seventh lens disposed on the second side of the aperture stop, the seventh lens being manufactured from thermoplastic; and
an eighth lens disposed on the second side of the aperture stop, the eighth lens being manufactured from thermoplastic.
14 . The projector device of claim 13 , wherein:
the fourth lens, the third lens, and the sixth lens are focusing elements of the projector device; and
the seventh lens and the eighth lens are zoom compensating elements of the projector device.
15 . The projector device of claim 13 , wherein:
the first lens comprises biconvex lens and a negative meniscus lens;
the second lens comprises a biconcave lens;
the third lens comprises a biconcave lens;
the fourth lens comprises a biconvex lens;
the fifth lens comprises a positive meniscus lens;
the sixth lens comprises a biconcave lens;
the seventh lens comprises a biconvex lens; and
the eighth lens comprises a positive meniscus lens.
16 . A projector device comprising:
a light source;
a digital micromirror device;
a lens system positioned and arranged to receive light from the light source via the digital micromirror device, the lens system including:
an aperture stop,
a first lens manufactured from a first material and being disposed on a first side of the aperture stop, and
a second lens manufactured from a second material and being disposed on a second side of the aperture stop that is opposite the first side of the aperture stop, the second lens having:
a first surface oriented towards the aperture stop, the first surface being both refractive and diffractive to light passing through the second lens, where features formed within the first surface contribute to light diffraction, and
a second surface opposite the first surface.
17 . The projector device of claim 16 , wherein:
the first material comprises glass; and
the second lens comprises thermoplastic.
18 . The projector device of claim 16 , wherein the second lens comprises a positive meniscus lens or a biconvex lens.
19 . The projector device of claim 16 , further comprising at least one of:
one or more third lenses disposed on the first side of the aperture stop, the one or more third lenses being manufactured from the second material; or
one or more fourth lenses disposed on the second side of the aperture stop, the one or more fourth lenses being manufactured from the second material.
20 . The projector device of claim 19 , wherein at least one of the second lens, the one or more third lenses, or the one or more fourth lenses includes an aspheric surface.