Patent · US Expired

Dichroic pentaprism for separating or combining frequency bands of electromagnetic energy

US5828497A · kind A · utility

4Cited by
8References
21Claims
0Family size

Assignee

Inventors

Key dates

Filing dateFeb 26, 1997
Grant dateOct 27, 1998
Priority date
Expiry dateFeb 26, 2017

Classification

  • Technology area (CPC G)Physics
  • CPC primaryG02B27/1006
  • WIPO fieldOptics
  • WIPO sectorInstruments

Abstract

A system (50) for separating and combining frequency bands (64, 74, 78) from a beam (62) of electromagnetic energy adapted for use with a beam of white light (62) having a first (64), second (74) and third (78) frequency band. The inventive system (50) includes a first surface (58) for transmitting the first frequency band (64) and reflecting the second (70, 78) and third (70, 74) frequency bands. A second surface (60) reflects the second frequency band (74) and transmits the third (78) frequency band. A transparent support structure (52, 54, 56) supports the first surface (58) and the second surface (60) in a pre-determined orientation that provides for a low angle of incidence (66, 72) of electromagnetic energy impinging on the first surface (58) and the second surface (60) to minimize undesirable polarization effects. In a specific embodiment, the angle (66, 72) is 22.5 degrees. The predetermined orientation includes the first surface (58) angled with respect to the second surface (60) so that the first (64), second (74), and third (78) frequency bands have first (64), second (74), and third (78) separate paths respectively. In the illustrative embodiment, the support structure …

Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.