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US 11,237,304 B2Granted
Self-temperature focus compensation device
OwnerShi-Hwa Huanginventor
Life of this patent
Estimating the term…
Abstract
A self-temperature focus compensation device adapted to cooperate with a lens group and including at least one Fresnel lens group is provided. Each Fresnel lens group has zero focal power at a specific temperature and is a cemented lens. Each Fresnel lens group includes a first Fresnel lens and a second Fresnel lens. The first Fresnel lens has positive focal power. The second Fresnel lens has negative focal power. A sum of a focal power change of the at least one Fresnel lens group with a temperature change and a focal power change of the lens group with the temperature change is zero.
Claims16
A self-temperature focus compensation device, adapted to cooperate with a lens group, comprising:
- at least one Fresnel lens group, wherein each Fresnel lens group has zero focal power at a specific temperature, is a cemented lens, and comprises:
- a first Fresnel lens having positive focal power;
- and
- a second Fresnel lens having negative focal power, wherein
- a sum of a focal power change of the at least one Fresnel lens group with a temperature change and a focal power change of the lens group with the temperature change is zero,
- wherein focal power of the lens group is greater than zero, when a temperature of the self-temperature focus compensation device is greater than the specific temperature, a difference between focal power of the second Fresnel lens at the temperature and focal power of the second Fresnel lens at the specific temperature is greater than zero, and when the temperature of the self-temperature focus compensation device is less than the specific temperature, the difference between the focal power of the second Fresnel lens at the temperature and the focal power of the second Fresnel lens at the specific temperature is less than zero.
3 more elements
A self-temperature focus compensation device, adapted to cooperate with a lens group, comprising:
- at least one Fresnel lens group, wherein each Fresnel lens group has zero focal power at a specific temperature and comprises:
- a first Fresnel lens having positive focal power;
- and
- a second Fresnel lens having negative focal power, wherein air gaps of the first Fresnel lens and the second Fresnel lens along an optical axis of the Fresnel lens group of the first Fresnel lens and the second Fresnel lens are greater than zero;
- wherein
- a sum of a focal power change of the at least one Fresnel lens group with a temperature change and a focal power change of the lens group with the temperature change is zero,
- wherein focal power of the lens group is greater than zero, when a temperature of the self-temperature focus compensation device is greater than the specific temperature, a difference between focal power of the second Fresnel lens at the temperature and focal power of the second Fresnel lens at the specific temperature is greater than zero, and when the temperature of the self-temperature focus compensation device is less than the specific temperature, the difference between the focal power of the second Fresnel lens at the temperature and the focal power of the second Fresnel lens at the specific temperature is less than zero.
4 more elements
A self-temperature focus compensation device, adapted to cooperate with a lens group, comprising:
- at least one Fresnel lens group, wherein each Fresnel lens group has zero focal power at a specific temperature, is a cemented lens, and comprises:
- a first Fresnel lens having positive focal power;
- and
- a second Fresnel lens having negative focal power, wherein
- a sum of a focal power change of the at least one Fresnel lens group with a temperature change and a focal power change of the lens group with the temperature change is zero,
- wherein focal power of the lens group is less than zero, when a temperature of the self-temperature focus compensation device is greater than the specific temperature, a difference between focal power of the first Fresnel lens at the temperature and focal power of the first Fresnel lens at the specific temperature is less than zero, and when the temperature of the self-temperature focus compensation device is less than the specific temperature, the difference between the focal power of the first Fresnel lens at the temperature and the focal power of the first Fresnel lens at the specific temperature is greater than zero.
3 more elements
A self-temperature focus compensation device, adapted to cooperate with a lens group, comprising:
- at least one Fresnel lens group, wherein each Fresnel lens group has zero focal power at a specific temperature and comprises:
- a first Fresnel lens having positive focal power;
- and
- a second Fresnel lens having negative focal power, wherein air gaps of the first Fresnel lens and the second Fresnel lens along an optical axis of the Fresnel lens group of the first Fresnel lens and the second Fresnel lens are greater than zero;
- wherein
- a sum of a focal power change of the at least one Fresnel lens group with a temperature change and a focal power change of the lens group with the temperature change is zero, wherein focal power of the lens group is less than zero, when a temperature of the self-temperature focus compensation device is greater than the specific temperature, a difference between focal power of the first Fresnel lens at the temperature and focal power of the first Fresnel lens at the specific temperature is less than zero, and when the temperature of the self-temperature focus compensation device is less than the specific temperature, the difference between the focal power of the first Fresnel lens at the temperature and the focal power of the first Fresnel lens at the specific temperature is greater than zero.
3 more elements
Dependencies are inferred from the claim text.