Dr. David William Fletcher-Holmes Profile

Dr. David William Fletcher-Holmes

at PerkinElmer Inc

SPIE Involvement:

Author

Publications (6)

Proceedings Article | 23 March 2005 Paper

Spectral imaging in a snapshot

Andrew Harvey, David Fletcher-Holmes, Alistair Gorman, Kirsten Altenbach, Jochen Arlt, Nick Read

Proceedings Volume 5694, (2005) https://doi.org/10.1117/12.604609

KEYWORDS: IRIS Consortium, Imaging spectroscopy, Imaging systems, Image filtering, Wave plates, Optical filters, Polarizers, Optical filtering, Prisms, Blood

Read Abstract +

Proceedings Article | 6 December 2004 Paper

Imaging spectrometry at visible and infrared wavelengths using image replication

Andrew Harvey, David Fletcher-Holmes, Sean Kudesia, Ciaran Beggan

Proceedings Volume 5612, (2004) https://doi.org/10.1117/12.580059

KEYWORDS: IRIS Consortium, Wave plates, Image filtering, Imaging spectroscopy, Optical filters, Prisms, Polarizers, Optical filtering, Imaging systems, Infrared radiation

Read Abstract +

Proceedings Article | 2 July 2003 Paper

High-throughput snapshot spectral imaging in two dimensions

Andrew Harvey, David Fletcher-Holmes

Proceedings Volume 4959, (2003) https://doi.org/10.1117/12.485557

KEYWORDS: Imaging spectroscopy, Imaging systems, IRIS Consortium, Hyperspectral imaging, Wave plates, Image filtering, Optical filtering, Sensors, Detector arrays, Polarizers

Read Abstract +

Proceedings Article | 8 November 2002 Paper

Hyperspectral imaging for the detection of retinal diseases

Andrew Harvey, Joanne Lawlor, Andrew McNaught, John Williams, David Fletcher-Holmes

Proceedings Volume 4816, (2002) https://doi.org/10.1117/12.451693

KEYWORDS: Retina, Imaging spectroscopy, Eye, Signal to noise ratio, Veins, Arteries, Fourier transforms, Optical filters, Retinal scanning, Hyperspectral imaging

Read Abstract +

Hyperspectral imaging (HSI) shows great promise for the detection and classification of several diseases, particularly in the fields of "optical biopsy" as applied to oncology, and functional retinal imaging in ophthalmology. In this paper, we discuss the application of HSI to the detection of retinal diseases and technological solutions that address some of the fundamental difficulties of spectral imaging within the eye. HSI of the retina offers a route to non-invasively deduce biochemical and metabolic processes within the retina. For example it shows promise for the mapping of retinal blood perfusion using spectral signatures of oxygenated and deoxygenated hemoglobin. Compared with other techniques using just a few spectral measurements, it offers improved classification in the presence of spectral cross-contamination by pigments and other components within the retina. There are potential applications for this imaging technique in the investigation and treatment of the eye complications of diabetes, and other diseases involving disturbances to the retinal, or optic-nerve-head circulation. It is well known that high-performance HSI requires high signal-to-noise ratios (SNR) whereas the application of any imaging technique within the eye must cope with the twin limitations of the small numerical aperture provided by the entrance pupil to the eye and the limit on the radiant power at the retina. We advocate the use of spectrally-multiplexed spectral imaging techniques (the traditional filter wheel is a traditional example). These approaches enable a flexible approach to spectral imaging, with wider spectral range, higher SNRs and lower light intensity at the retina than could be achieved using a Fourier-transform (FT) approach. We report the use of spectral imaging to provide calibrated spectral albedo images of healthy and diseased retinas and the use of this data for screening purposes. These images clearly demonstrate the ability to distinguish between oxygenated and deoxygenated hemoglobin using spectral imaging and this shows promise for the early detection of various retinopathies.

Proceedings Article | 8 November 2002 Paper

Snapshot foveal hyperspectral imager

David Fletcher-Holmes, Andrew Harvey

Proceedings Volume 4816, (2002) https://doi.org/10.1117/12.451617

KEYWORDS: Imaging systems, Hyperspectral imaging, Calibration, Spectral resolution, Charge-coupled devices, Optical fibers, Sensors, Fiber couplers, Signal to noise ratio, Multiplexing

Read Abstract +

Proceedings Article | 8 November 2002 Paper

Birefringent Fourier-transform imaging spectrometer

David Fletcher-Holmes, Andrew Harvey

Proceedings Volume 4816, (2002) https://doi.org/10.1117/12.451611

KEYWORDS: Prisms, Fourier transforms, Spectroscopy, Sensors, Signal to noise ratio, Interferometers, Calibration, Mirrors, Polarization, Modulation

Read Abstract +

Showing 5 of 6 publications

View contact details

UPDATE YOUR PROFILE

Is this your profile? Update it now.

Sign into your SPIE.org account

Don’t have a profile and want one?

Create an account on SPIE.org

Keywords/Phrases

Search In:

Publication Years