US6421164B2
Expired / Lapsed
US
⏱️ 0.0 years remaining
Interferometeric imaging with a grating based phase control optical delay line
Assignee: Massachusetts Institute of Technology
•
Filing: 2001-06-13
•
Granted: 2002-07-16
•
Expires: 2021-06-13
Abstract
Abstract An apparatus for performing high speed scanning of an optical delay and its application for performing optical interferometry, ranging, and imaging, including cross sectional imaging using optical coherence tomography, is disclosed. The apparatus achieves optical delay scanning by using diffractive optical elements in conjunction with imaging optics. In one embodiment a diffraction grating disperses an optical beam into different spectral frequency or wavelength components which are collimated by a lens. A mirror is placed one focal length away from the lens and the alteration of the grating groove density, the grating input angle, the grating output angle, and/or the mirror tilt produce a change in optical group and phase delay. This apparatus permits the optical group and phase delay to be scanned by scanning the angle of the mirror. In other embodiments, this device permits optical delay scanning without the use of moving parts.
Inventors
- 👤 Guillermo Tearney
- 👤 Brett E. Bouma
- 👤 James G. Fujimoto
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-26 16:00
CPC Classifications
A; A61; A61B; A61B1/00; A61B1/00163; A61B1/00172; A61B1/00174; A61B1/00183; A61B3/00; A61B3/10; A61B3/1005; A61B3/102; A61B3/12; A61B3/1225; A61B5/00; A61B5/0059; A61B5/0062; A61B5/0064; A61B5/0066; A61B5/68; A61B5/6846; A61B5/6847; A61B5/6852; B; B82; B82Y; B82Y15/00; G; G01; G01B; G01B11/00; G01B11/002; G01B11/02; G01B11/026; G01B11/08; G01B11/12; G01B11/24; G01B11/2441; G01B9/00; G01B9/02; G01B9/02001; G01B9/02002; G01B9/0209; G01B9/02091; G01J; G01J1/00; G01N; G01N21/00; G01N21/17; G01N21/47; G01N21/4795; G02; G02B; G02B26/00; G02B26/06; G02B27/00; G02B27/42; G02B27/4233; G02B27/4244; G02B27/4255; G02B5/00; G02B5/18; G02B5/1828; G11; G11B; G11B7/00; G11B7/004; G11B7/005; G11B7/08; G11B7/085; G11B7/08547; G11B7/08564; G11B7/12; G11B7/125; G11B7/127; G11B7/135; G11B7/1353; A61B1/00064; A61B1/00071; A61B1/0008; A61B1/00096; A61B2562/00; A61B2562/02; A61B2562/0233; A61B2562/0242; A61B5/0082; A61B5/0084; A61B5/44; A61B5/441; G01B2290/00; G01B2290/20; G01B2290/35; G11B2007/0003; G11B2007/0009; G11B2007/0013; G11B7/24; H; H01; H01S; H01S5/00; H01S5/10; H01S5/14; H01S5/141
Claims Analysis
Total Claims: 11
Claim 1
Independent Claim
129 words
A method for producing an image of a sample, comprising: providing an optical delay line apparatus, the optical delay line apparatus comprising: an optical input; an optical output; and a plurality of optical elements in optical communication with each other; guiding an optical signal having an optical spectrum from said optical input to said optical output by said plurality of optical elements, wherein at least one of said plurality of optical elements is a dispersive element and wherein at least one of said plurality of optical elements is adjustable; spatially dispersing the optical spectrum produced by the sample to provide a spatially dispersed optical signal; and, repetitively scanning at least one of a phase delay and a group delay of the spatially dispersed optical signal to produce an image.
Claim 2
Independent Claim
129 words
A method for producing an image of a sample, comprising: providing an optical delay line apparatus, the optical delay line apparatus comprising: an optical input; an optical output; and a plurality of optical elements in optical communication with each other; guiding an optical signal having an optical spectrum from said optical input to said optical output by said plurality of optical elements, wherein at least one of said plurality of optical elements is a dispersive element and wherein at least one of said plurality of optical elements is adjustable; spatially dispersing the optical spectrum produced by the sample to provide a spatially dispersed optical signal; and, repetitively scanning at least one of a phase delay and a group delay of the spatially dispersed optical signal to produce an image.
Claim 3
Dependent Claim
78 words
The method according to claim 1 , wherein the optical delay line apparatus comprises an optical imaging module and a reflective element, each in optical communication with said dispersive element, the method further comprising generating an angularly dispersed optical signal having spectral components by said dispersive element; producing an image of the angularly dispersed optical signal by said optical imaging module at said reflective element; and, altering the angle of said reflective element to adjust the group delay.
Claim 4
Dependent Claim
38 words
The method according to claim 1 , wherein said dispersive element is a diffraction grating, the method further comprising adjusting the group delay by altering the relative angle between the diffraction grating normal and the incident light beam.
Claim 5
Dependent Claim
52 words
The method according to claim 1 , wherein said dispersive element has a spatially periodic structure, the method further comprising spatially dispersing wavelength components of the optical spectrum of the optical signal by said spatially periodic structure; and, adjusting the group delay by altering the spatially periodic structure of said dispersive element.
Claim 6
Dependent Claim
43 words
The method according to claim 1 , wherein said dispersive element comprises an acousto-optic modulator having an adjustable spatially periodic structure, the method further comprising varying the response of the periodic structure to a radio frequency drive waveform received by said acousto-optic modulator.
Claim 7
Dependent Claim
30 words
The method according to claim 5 , further comprising repetitively altering said radio frequency drive waveform to produce a repetitive and substantially constant rate of change of the group delay.
Claim 8
Dependent Claim
31 words
The method according to claim 5 , further comprising repetitively altering said radio frequency drive waveform to produce a repetitive change in group delay with a substantially constant optical throughput efficiency.
Claim 9
Dependent Claim
39 words
The method according to claim 5 , wherein another of said plurality of optical elements is a double-pass mirror, wherein the method further comprises positioning said double-pass mirror; and, receiving said spatially dispersed optical signal by said double-pass mirror.
Claim 10
Dependent Claim
40 words
The method according to claim 1 , further comprising interferometrically combining the optical signal transmitted through said optical delay line with a portion of the optical signal not transmitted through said delay line to achieve a non-zero frequency heterodyne signal.
Claim 11
Dependent Claim
33 words
The method according to claim 1 , further comprising adjusting at least one of said plurality of optical elements to independently affect the phase delay and the group delay of said optical signal.
References Cited (Backward Citations)
US3532037A
Cited
US3556079A
Cited
US3549239A
Cited
US3961841A
Cited
US3710798A
Cited
US3769963A
Cited
US3905703A
Cited
US3821510A
Cited
US3961621A
Cited
US3906953A
Cited
US4058114A
Cited
US4091814A
Cited
US4141362A
Cited
US4336809A
Cited
US4596466A
Cited
US4420260A
Cited
US4612938A
Cited
US4545390A
Cited
US4554929A
Cited
US4652129A
Cited
US4873989A
Cited
US4669465A
Cited
US4638800A
Cited
US4648892A
Cited
US5318024A
Cited
US4669467A
Cited
US5106387A
Cited
US4718417A
Cited
US4913142A
Cited
US4619274A
Cited
DE3527245A1
Cited
US5196004A
Cited
DE3627420A1
Cited
US4796994A
Cited
US4748986A
Cited
US4958930A
Cited
US4721117A
Cited
GB2191855A
Cited
US4819632A
Cited
US4887606A
Cited
US5005584A
Cited
US4844062A
Cited
US4928005A
Cited
US4900314A
Cited
US4834102A
Cited
US5715825A
Cited
US5201317A
Cited
US4969736A
Cited
US4899733A
Cited
US5562100A
Cited
US5421337A
Cited
US5032722A
Cited
US5114403A
Cited
US5034613A
Cited
US5094534A
Cited
US5110211A
Cited
US5133598A
Cited
US5501599A
Cited
US5197470A
Cited
US5305759A
Cited
US5157457A
Cited
US5053033A
Cited
US5434669A
Cited
US5155549A
Cited
US5202745A
Cited
US5257991A
Cited
US5401270A
Cited
EP0501034A1
Cited
US5303026A
Cited
US5465147A
Cited
US6134003A
Cited
US6111645A
Cited
US5459570A
Cited
US5321501A
Cited
US6160826A
Cited
US5370649A
Cited
US5787890A
Cited
US5291267A
Cited
US5268741A
Cited
US5217456A
Cited
US5365335A
Cited
US5251198A
Cited
US5390023A
Cited
US5268738A
Cited
US5325177A
Cited
US5383467A
Cited
US5439000A
Cited
US5601087A
Cited
US5366456A
Cited
DE4309056A1
Cited
US5421339A
Cited
US5623932A
Cited
US5354294A
Cited
US5555087A
Cited
US5428699A
Cited
US5490521A
Cited
US5495541A
Cited
US5570182A
Cited
US5509917A
Cited
US5537499A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 2005-07-15 | 2006-01-14 | 2006-07-16 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 2009-07-15 | 2010-01-14 | 2010-07-16 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2013-07-15 | 2014-01-14 | 2014-07-16 | $7700.00 | Window Closed / Lapsed |