Del Mar Photonics
MINIATURE HIGH THROUGHPUT UV/VISIBLE/NIR SPECTROMETER
Spectral methods are currently widely used in research, medicine, quality control, hazards detection and other fields. Real time spectroscopy using multichannel detectors is the backbone of most such applications in the UV/Visible/NIR regions. Some sort of the dispersive element (prism or diffraction grating) is usually used in these devices to break the incoming light into spectral components and distribute them across the detector array. But it is not the only way to make use of the multichannel detection technique. In fact back in sixties when the only multichannel detector available was the photographic plate several works in the field of holographic spectroscopy appeared. The spectral hologram (known now as the static interferogram) created by the shearing or tilt interferometer was recorded using photographic methods and the spectrum was reproduced with the aid of the optical Fourier transform. These early devices were called holographic Fourier transform spectrometers (HFTS) due to the fact that the spectral hologram was actually the Fourier transform of the spectrum. Advances in the computing and in the multichannel detectors in seventies resulted in holographic spectroscopy all but forgotten.
Only in late eighties the holographic spectroscopy found its use in the remote sensing thanks to the ultimate throughput advantage. In contrast to the dispersive spectrometer, where the spectral resolution dictates the size of the entrance slit, in the holographic FTS there is no intrinsic restriction on the size of the radiation source. Still the instruments used in the remote sensing are quite complicated optical systems designed for precise synchronization between the scene movement and the detection process. No commercial products are available using holographic spectroscopy and sufficiently versatile to be easily adaptable for various applications.
This market niche is possible to fill now with the introduction of the ĀNUENUE - patented miniature Holographic Fourier Transform Spectrometer for the UV/Visible/NIR based on the single piece Sagnac interferometer. This versatile instrument can be used with any CCD or CMOS camera.
The basic version made from BK7 glass utilizing spherical lenses has following characteristics.
|Spectral coverage (nm)
Throughput (mm2 srad)
|340 – 1000
260 (202 theoretical limit)
The ĀNUENUE throughput parameter is 280 times larger than for the spectrograph with the same resolving power. Even an order of magnitude throughput value can be achieved if aspheric lenses are used in the interferometer. With the throughput that large the signal-to-noise ratio achievable with this instrument is significantly better than for the spectrograph using the shot noise limited detectors.
Examples of spectra measured with the ĀNUENUE spectrometer are shown below. A broad spectral coverage is confirmed by successful detection both the neon lamp spectrum and the emission of the UV diode.
Spectra of neon lamp (red trace) and of the UV diode (blue trace) measured with the ĀNUENUE HFTS spectrometer.
The large throughput advantage of the novel instrument determines its possible applications. One example is the quality control. A color camera is capable to detect spectral information only in three spectral regions – red, green, and blue. With the new instrument the product can be characterized in 100 different spectral regions. The large observation spot makes the testing procedure hundreds times faster than with the dispersive spectrometer. Another possible application is to simultaneously monitor spectral signatures from many different locations. A large number of fiber optic inputs can be bundled together and fed into the instrument. The presence of the characteristic spectral signature, such as the luminescence band of the hazardous chemical will be thus simultaneously monitored with a single instrument. Another possible application of the new instrument is in the medicine. Fluorescent markers attached to the malign tissue can be detected from a larger area making the medical procedure faster and less expansive.
Request a quote for basic ĀNUENUE HFTS spectrometer.
Request a quote for custom
spectrometer, optimized for your application.
For custom quote please indicate:
Spectral coverage (nm)
Throughput (mm2 srad)
Estiamted annual volume
We also manufacture OEM and private label HFTS.
Techical paper: Miniaturization of Holographic Fourier-transform spectrometers
Where Del Mar Photonics product's names come from?
Del Mar means 'by the sea", and Photonics is all about optical waves. So we decided to choose terms popular in surfing and sailing communities. Our femtosecond lasers, amplifiers and systems are named after popular surf breaks around the world, and many other products names after sailing and nautical terms. ĀNUENUE HFTS spectrometer name means Rainbow in Hawaiian language.
Del Mar Photonics, Inc.
4119 Twilight Ridge
San Diego, CA 92130
tel: (858) 876-3133
fax: (858) 630-2376