Near-infrared imaging lens
US9869847B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Feb 7, 2016 |
| Grant date | Jan 16, 2018 |
| Priority date | — |
| Expiry date | Apr 28, 2036 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG02B27/0018
- WIPO fieldOptics
- WIPO sectorInstruments
Abstract
An optical system for operation at a target near-infrared (NIR) wavelength in imaging an object onto an image plane. The system includes the following optical elements, arranged in order from object side to image side: a first lens, including a first material having a first index of refraction at the target NIR wavelength and having a positive refractive power; a second lens comprising the first material and having a meniscus shape; a third lens comprising the first material and having a meniscus shape; and a fourth lens, including a second material having a second index of refraction at the target NIR wavelength that is lower than the first index of refraction, and having front and rear surfaces of an aspheric form. The aspheric coefficients are chosen so that rays are not totally internally reflected within the fourth lens to impinge on the image plane.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.