US 9,810,825 B2
Curved volume phase holographic (VPH) diffraction grating with tilted fringes and spectrographs using same
J. Christopher Clemens, Chapel Hill, NC (US); and Darragh Evelyn Anthony Adam O'Donoghue, Cape Town (ZA)
Assigned to The University of North Carolina at Chapel Hill, Chapel Hill, NC (US)
Filed by The University of North Carolina at Chapel Hill, Chapel Hill, NC (US)
Filed on Jul. 15, 2013, as Appl. No. 13/942,306.
Claims priority of provisional application 61/671,515, filed on Jul. 13, 2012.
Prior Publication US 2014/0022615 A1, Jan. 23, 2014
Int. Cl. G02B 5/32 (2006.01); G01J 3/18 (2006.01); B29D 11/00 (2006.01); G01J 3/02 (2006.01); G01J 3/10 (2006.01); G01J 3/45 (2006.01); G03H 1/00 (2006.01); G03H 1/02 (2006.01); G03H 1/04 (2006.01); G03H 1/18 (2006.01)
CPC G02B 5/32 (2013.01) [B29D 11/00769 (2013.01); G01J 3/021 (2013.01); G01J 3/10 (2013.01); G01J 3/1838 (2013.01); G01J 3/45 (2013.01); G03H 1/0005 (2013.01); G03H 1/0248 (2013.01); G03H 1/041 (2013.01); G03H 1/181 (2013.01); G01J 2003/102 (2013.01); G01J 2003/452 (2013.01); G03H 2001/026 (2013.01); G03H 2001/0439 (2013.01); G03H 2001/185 (2013.01)] 11 Claims
OG exemplary drawing
1. A spectrograph comprising:
a first curved volume phase holographic (VPH) transmission diffraction grating comprising a first curved surface through which light to be diffracted enters the grating, a second curved second curved surface through which diffracted light exits the grating, and an interior region located between the first and second curved surfaces:
the interior region having tilted fringes holographically recorded within the interior region for diffracting at least some light that passes through the first surface and the interior region, wherein the tilted fringes have tilt angles θ recorded to be different from each other and substantially constant with respect to light rays incident on the first surface that impinge on the fringes;
the second curved surface for passing the light diffracted by the fringes from the interior region through the second surface to a region exterior to the first curved VPH transmission diffraction grating on the side opposite the first curved surface; and
optics for directing the light to and from the first curved VPH transmission diffraction grating.