Coherent light generators – Particular beam control device – Modulation
Reexamination Certificate
2005-10-18
2005-10-18
Harvey, Minsun O. (Department: 2828)
Coherent light generators
Particular beam control device
Modulation
C372S026000, C372S028000, C372S101000, C372S108000
Reexamination Certificate
active
06956878
ABSTRACT:
A method and apparatus for reducing speckle uses polarization averaging. A polarizing beam splitter divides a first polarized laser output into a second polarized laser output and a third polarized laser output. A plurality of mirrors creates an optical path difference between the second and third polarized laser outputs. The optical path difference is at least about a coherence length for the first polarized laser output. The second and third polarized laser outputs are combined into a fourth laser output, which illuminates a depolarizing screen. If a human eye or an optical system having a intensity detector views the depolarizing screen, the eye or the intensity detector will detect reduced speckle, which results from uncorrelated speckle patterns created by the second polarized laser output and the third polarized laser output. A first alternative embodiment of the invention functions without the optical path difference being at least about the coherence length. In the first alternative embodiment, a piezoelectric transducer varies an optical path length by at least about a half wavelength of the first polarized laser output. By varying the optical path length by a sufficient frequency, the eye or the intensity detector will detect the reduced speckle. A second alternative embodiment combines two orthogonally polarized laser outputs, from two lasers, into a combined laser output. The combined laser output illuminates the depolarizing screen. A third alternative embodiment rotates the first laser output with a rotation frequency to form a rotating polarized laser output, which illuminates the depolarizing screen.
REFERENCES:
patent: 3941456 (1976-03-01), Schilz et al.
patent: 4034399 (1977-07-01), Drukier et al.
patent: 4035068 (1977-07-01), Rawson
patent: 4067129 (1978-01-01), Abramson et al.
patent: 4084437 (1978-04-01), Finnegan
patent: 4090219 (1978-05-01), Ernstoff et al.
patent: 4093346 (1978-06-01), Nishino et al.
patent: 4093921 (1978-06-01), Buss
patent: 4093922 (1978-06-01), Buss
patent: 4100579 (1978-07-01), Ernstoff
patent: 4103273 (1978-07-01), Keller
patent: 4126380 (1978-11-01), Borm
patent: 4127322 (1978-11-01), Jacobson et al.
patent: 4135502 (1979-01-01), Peck
patent: 4139257 (1979-02-01), Matsumoto
patent: 4143943 (1979-03-01), Rawson
patent: 4163570 (1979-08-01), Greenaway
patent: 4184700 (1980-01-01), Greenaway
patent: 4185891 (1980-01-01), Kaestner
patent: 4190855 (1980-02-01), Inoue
patent: 4195915 (1980-04-01), Lichty et al.
patent: 4205428 (1980-06-01), Ernstoff et al.
patent: 4211918 (1980-07-01), Nyfeler et al.
patent: 4223050 (1980-09-01), Nyfeler et al.
patent: 4225913 (1980-09-01), Bray
patent: 4249796 (1981-02-01), Sincerbox et al.
patent: 4250217 (1981-02-01), Greenaway
patent: 4250393 (1981-02-01), Greenaway
patent: 4256787 (1981-03-01), Shaver et al.
patent: 4257016 (1981-03-01), Kramer, Jr. et al.
patent: 4290672 (1981-09-01), Whitefield
patent: 4295145 (1981-10-01), Latta
patent: 4311999 (1982-01-01), Upton et al.
patent: 4327411 (1982-04-01), Turner
patent: 4327966 (1982-05-01), Bloom
patent: 4331972 (1982-05-01), Rajchman
patent: 4336982 (1982-06-01), Rector, Jr.
patent: 4338660 (1982-07-01), Kelley et al.
patent: 4343535 (1982-08-01), Bleha, Jr.
patent: 4346965 (1982-08-01), Sprague et al.
patent: 4348079 (1982-09-01), Johnson
patent: 4355463 (1982-10-01), Burns
patent: 4361384 (1982-11-01), Bosserman
patent: 4369524 (1983-01-01), Rawson et al.
patent: 4374397 (1983-02-01), Mir
patent: 4389096 (1983-06-01), Hori et al.
patent: 4391490 (1983-07-01), Hartke
patent: 4396246 (1983-08-01), Holman
patent: 4398798 (1983-08-01), Krawczak et al.
patent: 4400740 (1983-08-01), Traino et al.
patent: 4408884 (1983-10-01), Kleinknecht et al.
patent: 4414583 (1983-11-01), Hooker, III
patent: 4417386 (1983-11-01), Exner
patent: 4418397 (1983-11-01), Brantingham et al.
patent: 4420717 (1983-12-01), Wallace et al.
patent: 4422099 (1983-12-01), Wolfe
patent: 4426768 (1984-01-01), Black et al.
patent: 4430584 (1984-02-01), Someshwar et al.
patent: 4435041 (1984-03-01), Torok et al.
patent: 4440839 (1984-04-01), Mottier
patent: 4443819 (1984-04-01), Funada et al.
patent: 4443845 (1984-04-01), Hamilton et al.
patent: 4447881 (1984-05-01), Brantingham et al.
patent: 4454591 (1984-06-01), Lou
patent: 4456338 (1984-06-01), Gelbart
patent: 4460907 (1984-07-01), Nelson
patent: 4462046 (1984-07-01), Spight
patent: 4467342 (1984-08-01), Tower
patent: 4468725 (1984-08-01), Venturini
patent: 4483596 (1984-11-01), Marshall
patent: 4484188 (1984-11-01), Ott
patent: 4487677 (1984-12-01), Murphy
patent: 4492435 (1985-01-01), Banton et al.
patent: 4503494 (1985-03-01), Hamilton et al.
patent: 4511220 (1985-04-01), Scully
patent: 4538883 (1985-09-01), Sprague et al.
patent: 4545610 (1985-10-01), Lakritz et al.
patent: 4556378 (1985-12-01), Nyfeler et al.
patent: 4558171 (1985-12-01), Gantley et al.
patent: 4561011 (1985-12-01), Kohara et al.
patent: 4561044 (1985-12-01), Ogura et al.
patent: 4566935 (1986-01-01), Hornbeck
patent: 4567585 (1986-01-01), Gelbart
patent: 4571041 (1986-02-01), Gaudyn
patent: 4571603 (1986-02-01), Hornbeck et al.
patent: 4577932 (1986-03-01), Gelbart
patent: 4577933 (1986-03-01), Yip et al.
patent: 4588957 (1986-05-01), Balant et al.
patent: 4590548 (1986-05-01), Maytum
patent: 4594501 (1986-06-01), Culley et al.
patent: 4596992 (1986-06-01), Hornbeck
patent: 4615595 (1986-10-01), Hornbeck
patent: 4623219 (1986-11-01), Trias
patent: 4636039 (1987-01-01), Turner
patent: 4636866 (1987-01-01), Hattori
patent: 4641193 (1987-02-01), Glenn
patent: 4645881 (1987-02-01), LeToumelin et al.
patent: 4646158 (1987-02-01), Ohno et al.
patent: 4649085 (1987-03-01), Landram
patent: 4649432 (1987-03-01), Watanabe
patent: 4652932 (1987-03-01), Miyajima et al.
patent: 4655539 (1987-04-01), Caulfield et al.
patent: 4660938 (1987-04-01), Kazan
patent: 4661828 (1987-04-01), Miller, Jr. et al.
patent: 4662746 (1987-05-01), Hornbeck
patent: 4663670 (1987-05-01), Ito et al.
patent: 4687326 (1987-08-01), Corby, Jr.
patent: 4698602 (1987-10-01), Armitage
patent: 4700276 (1987-10-01), Freyman et al.
patent: 4707064 (1987-11-01), Dobrowolski et al.
patent: 4709995 (1987-12-01), Kuribayashi et al.
patent: 4710732 (1987-12-01), Hornbeck
patent: 4711526 (1987-12-01), Hennings et al.
patent: 4714326 (1987-12-01), Usui et al.
patent: 4717066 (1988-01-01), Goldenberg et al.
patent: 4719507 (1988-01-01), Bos
patent: 4721629 (1988-01-01), Sakai et al.
patent: 4722593 (1988-02-01), Shimazaki
patent: 4724467 (1988-02-01), Yip et al.
patent: 4728185 (1988-03-01), Thomas
patent: 4743091 (1988-05-01), Gelbart
patent: 4744633 (1988-05-01), Sheiman
patent: 4747671 (1988-05-01), Takahashi et al.
patent: 4751509 (1988-06-01), Kubota et al.
patent: 4761253 (1988-08-01), Antes
patent: 4763975 (1988-08-01), Scifres et al.
patent: 4765865 (1988-08-01), Gealer et al.
patent: 4772094 (1988-09-01), Sheiman
patent: 4797694 (1989-01-01), Agostinelli et al.
patent: 4797918 (1989-01-01), Lee et al.
patent: 4801194 (1989-01-01), Agostinelli et al.
patent: 4803560 (1989-02-01), Matsunaga et al.
patent: 4804641 (1989-02-01), Arlt et al.
patent: 4807021 (1989-02-01), Okumura
patent: 4807965 (1989-02-01), Garakani
patent: 4809078 (1989-02-01), Yabe et al.
patent: 4811082 (1989-03-01), Jacobs et al.
patent: 4811210 (1989-03-01), McAulay
patent: 4814759 (1989-03-01), Gombrich et al.
patent: 4817850 (1989-04-01), Wiener-Avnear et al.
patent: 4824200 (1989-04-01), Isono et al.
patent: 4827391 (1989-05-01), Sills
patent: 4829365 (1989-05-01), Eichenlaub
patent: 4836649 (1989-06-01), Ledebuhr et al.
patent: 4856863 (1989-08-01), Sampsell et al.
patent: 4856869 (1989-08-01), Sakata et al.
patent: 4859012 (1989-08-01), Cohn
patent: 4859060 (1989-08-01), Katagiri et al.
patent: 4866488 (1989-09-01), Frensley
patent: 4882683 (1989-11-01), Rupp et al.
patent: 4893509 (1990-01-01), MacIver et al.
patent: 4896325 (1990-01-01), Coldren
patent: 4896948 (1990-01-01), Dono et al.
patent: 4897708 (1990-01-01), Clements
patent: 4902083 (1990-02-01), Wells
patent: 4915463 (1990-04-01), Barbee, Jr.
patent: 4915479 (1990-04-
Harvey Minsun O.
Okamoto & Benedicto LLP
Rodriguez Armando
Silicon Light Machines Corporation
LandOfFree
Method and apparatus for reducing laser speckle using... does not yet have a rating. At this time, there are no reviews or comments for this patent.
If you have personal experience with Method and apparatus for reducing laser speckle using..., we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Method and apparatus for reducing laser speckle using... will most certainly appreciate the feedback.
Profile ID: LFUS-PAI-O-3453483