Projection lens
AssigneeYoung Optics Inc.
InventorsShuo-Chieh Chang, Ching-Lung Lai, Hsin-Te Chen, Kuo-Chuan Wang
Life of this patent
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Abstract
The disclosure provides a projection lens including a first lens set and a second lens set disposed sequentially from a magnified side to a reduced side. The first lens set and the second lens set are separated by a minimum inner diameter of a lens barrel. The first lens set includes 4 to 6 spherical lenses, and a refractive power of the first lens set is negative. The second lens set includes 4 to 6 lenses, where one of the lenses is an aspheric lens, and a refractive power of the second lens set is positive. A transmittance of the projection lens at a wavelength of 365 nm is greater than or equal to 75%.
Claims14
A projection lens, comprising:
- a first lens set and a second lens set, disposed in sequence from a magnified side to a reduced side, wherein:
- the first lens set and the second lens set are separated by a minimum inner diameter of a lens barrel;
- the first lens set comprises 4 to 6 spherical lenses, and a refractive power of the first lens set is negative;
- the second lens set comprises 4 to 6 lenses, one of the lenses is an aspheric lens, and a refractive power of the second lens set is positive;
- and
- the projection lens comprises a transmittance greater than or equal to 75% at a wavelength of 365 nm,
- wherein an effective focal length of the projection lens is greater than or equal to 8 and less than or equal to 14,
- wherein a total length of the projection lens is fixed, the effective focal length of the projection lens is fixed, and a zoom ratio of the projection lens is substantially equal to 1,
- wherein the projection lens does not comprise a cemented lens,
- wherein a distance between two lenses of the projection lens is between 0.001 to 0.01 mm,
- wherein the projection lens does not comprise an infrared filter.
A projection lens comprising a first lens set and a second lens set disposed in sequence from a magnified side to a reduced side, wherein
- the first lens set comprises 3 to 5 spherical lenses, a refractive power of the first lens set is negative, and the first lens set is disposed in a first lens barrel;
- the second lens set comprises an aspheric lens and comprises 5 to 7 lenses, a refractive power of the second lens set is positive, and the second lens set is disposed in a second lens barrel;
- and
- the projection lens comprises a transmittance greater than or equal to 75% at a wavelength of 365 nm,
- wherein an effective focal length of the projection lens is greater than or equal to 8 and less than or equal to 14,
- wherein a total length of the projection lens is fixed, the effective focal length of the projection lens is fixed, and a zoom ratio of the projection lens is substantially equal to 1,
- wherein the projection lens does not comprise a cemented lens,
- wherein a distance between two lenses of the projection lens is between 0.001 to 0.01 mm,
- wherein the projection lens does not comprise an infrared filter.
Dependencies are inferred from the claim text.