Performance of a Holographic Supernotch Filter

Results are presented of a comparative evaluation of a holographic supernotch filter (HSNF) and a holographic notch filter (HNF) as a Rayleigh line rejection filter for Raman spectroscopy. The filter permits acquisition of both Stokes and anti-Stokes spectra down to ±200 cm−1 shift from excitation simultaneously, without filter angle adjustment. With slight angle adjustment, spectra can be recorded as close as 41 cm−1 from the excitation line. Performance of the HSNF is evaluated by measuring the low-frequency Raman spectra of Tb2(MoO4)3, water, and naphthalene.

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Holographic Notch Filter for Low-Wavenumber Stokes and Anti-Stokes Raman Spectroscopy

Applied Spectroscopy ◽

10.1366/0003702914335553 ◽

1991 ◽

Vol 45 (9) ◽

pp. 1533-1536 ◽

Cited By ~ 60

Author(s):

Bijun Yang ◽

Michael D. Morris ◽

Harry Owen

Keyword(s):

Raman Spectroscopy ◽

Notch Filter ◽

Holographic Notch Filter ◽

Anti Stokes

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Potassium Vapor Near-IR Laser Line Rejection Filter for Raman Spectroscopy

Applied Spectroscopy ◽

10.1366/0003702934048550 ◽

1993 ◽

Vol 47 (1) ◽

pp. 69-74 ◽

Cited By ~ 15

Author(s):

M. J. Pelletier

Keyword(s):

Raman Spectroscopy ◽

Raman Spectra ◽

Laser Wavelength ◽

Laser Line ◽

Near Ir ◽

Ir Laser ◽

Rejection Filter ◽

Potassium Vapor ◽

Anti Stokes

A simple, inexpensive, near-IR laser line rejection filter using potassium vapor is described and characterized for Raman applications. Stokes and anti-Stokes Raman spectra, including the laser wavelength, were collected with the use of this filter. The cystine 9.6-cm−1 anti-Stokes band and the 14.9-cm−1 Stokes band were only weakly affected by the vapor filter, but the laser line was attenuated by more than 10 orders of magnitude. The laser line was completely removed from the spectra of weak elastic scatterers without significantly attenuating emission ±1.2 cm−1 from the laser line.

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Near-Infrared Raman Spectroscopy Using CCD Detection and a Semiconductor Bandgap Filter for Rayleigh Line Rejection

Applied Spectroscopy ◽

10.1366/0003702924124312 ◽

1992 ◽

Vol 46 (6) ◽

pp. 891-893 ◽

Cited By ~ 30

Author(s):

Alfons Schulte

Keyword(s):

Raman Spectroscopy ◽

Fourier Transform ◽

Raman Spectra ◽

Near Infrared ◽

Sapphire Laser ◽

Laser Line ◽

Rayleigh Line ◽

Rejection Filter ◽

Multichannel Detection ◽

Fourier Transform Raman

A novel application of a tuneable Ti: sapphire laser and a CdTe Rayleigh line rejection filter for near-infrared Raman spectroscopy employing a single grating spectrograph and multichannel detection is demonstrated. Raman spectra of liquid, solid, and photobiological samples have been measured within 75 cm−1 of the exciting laser line. At excitation wavelengths between 790 and 850 nm, a significant improvement in sensitivity over that for present Fourier transform Raman techniques has been obtained.

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Ultraviolet Raman Spectroscopy Using an Atomic Vapor Filter and Incoherent Excitation

Applied Spectroscopy ◽

10.1366/0003702924125320 ◽

1992 ◽

Vol 46 (3) ◽

pp. 395-400 ◽

Cited By ~ 17

Author(s):

M. J. Pelletier

Keyword(s):

Raman Spectroscopy ◽

Raman Spectrum ◽

Raman Spectra ◽

Optical Density ◽

Line Source ◽

Scattered Light ◽

Atomic Vapor ◽

Rejection Filter ◽

Uv Raman ◽

Anti Stokes

A far-UV line-rejection filter for Raman spectroscopy having an optical density greater than 5.5, a rejection bandwidth of only a few wavenumbers, and a transmission greater than 80% throughout the Stokes and anti-Stokes regions of the Raman spectrum is described. Raman spectra were collected with the use of this filter to remove elastically scattered light. Mercury penlamps were used for excitation. Good-quality spectra could be obtained with integration times as short as 1 second per wavenumber. The advantages of using an atomic line source rather than a laser-based source to excite far-UV Raman spectra are discussed.

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Construction and Operation of a dispersive Laser Raman Spectrograph using interference filter

Journal of Bangladesh Academy of Sciences ◽

10.3329/jbas.v32i1.2451 ◽

1970 ◽

Vol 32 (1) ◽

pp. 121-129

Author(s):

KM Abedin ◽

SFU Farhad ◽

MR Islam ◽

Aminul I Talukder ◽

AFMY Haider

Keyword(s):

Raman Spectra ◽

Notch Filter ◽

Ccd Camera ◽

Interference Filter ◽

Spectral Lines ◽

Quantitative Chemical Analysis ◽

Laser Raman ◽

Holographic Notch Filter ◽

Cooled Ccd ◽

Anti Stokes

A dispersive laser Raman system was designed and constructed using a helium-neon (He-Ne) laser as an excitation source, and an interference filter in the reflection mode for Raleigh filtering instead of the more common holographic notch filter. A commercially available spectrograph equipped with a cooled CCD camera was used to acquire the Raman spectra. The constructed laser Raman spectrograph was found to have excellent performance and sensitivity. Stokes Raman spectra of some common chemicals were acquired by the system, and the wavelengths of spectral lines agreed well with the literature values, within experimental error. The useful spectral range of the system is about 200-4000 cm-1. It was also possible to acquire anti-Stokes Raman spectra of one chemical (CCl4) without much difficulty. We hope to use the system for chemical identification of molecules as well as quantitative chemical analysis. To our knowledge, this is the first laser Raman system constructed in Bangladesh. doi: 10.3329/jbas.v32i1.2451 Journal of Bangladesh Academy of Sciences, Vol. 32, No. 1, 121-129, 2008

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