Speckle suppression in laser display using several partially coherent beams.
An optical scheme for speckle suppression using two or three partially coherent beams in a projection system is proposed. Diffractive optical elements (DOE) placed in the intermediate image plane create several beams carrying the image to a screen. Transparent plates of different thicknesses are placed in the Fourier plane of the projective lens and used for beam decorrelation. The coherence matrix algorithm for speckle suppression is used to calculate the speckle contrast ratio. It is shown that for a small decorrelation length and using the same maximum thickness of the transparent plates, two partially coherent beams would provide better suppression than three beams with different diffraction orders. However, for a large decorrelation length, the three beam setup provides better speckle suppression for all three colors examined with a suppression coefficient close to theoretical limits. Verification of speckle suppression using three-beam decorrelation is reported.
An
Seungdo
S
OS Division, SOM R&D and Biz. Group, Samsung Electro-Mechanics Co, Ltd, Suwon, Korea. seungdo.an@samsung.com
Lapchuk
Anatoliy
A
Yurlov
Victor
V
Song
Jonghyeong
J
Park
Heungwoo
H
Jang
Jaewook
J
Shin
Woocheol
W
Karpoltsev
Sergey
S
Yun
Sang Kyeong
SK
D003287:Contrast Media; D004867:Equipment Design; D005583:Fourier Analysis; D007089:Image Enhancement / Q000379:methods; D007090:Image Interpretation, Computer-Assisted / Q000379:methods; D007834:Lasers; D008027:Light; D055095:Optics and Photonics; D019047:Phantoms, Imaging; D015203:Reproducibility of Results; D012825:Silicon; D041623:Tomography, Optical Coherence / Q000295:instrumentation / Q000379:methods*; D014961:X-Ray Diffraction / Q000379:methods
D003287:Contrast Media; D012825:Silicon