Visible Light Spectroscopy

I have several spectrographs that work in the visible range. The most sophisticated is the one used for astronomical redshift measurements shown at right. It is a typical Cerzy-Turner design which uses a single order grating to image the spectrum on the CCD camera. The spectrum shown below covers only 100 angstroms which indicates the high resolution nature of this instrument. This spectrograph is capable of measuring changes in the spectrums position of 1 millionth of an inch. In order to do this all the components are mounted on granite and enclosed in a temperature stabilized box. For in depth info see www.spectrashift.com.

Spectrograph for measuring a stars velocity.Spectrograph for measuring a stars velocity.
100 angstrom high resolution spectrum used to measure redshift (which is the stars velocity).

The picture below left is from the next generation instrument I am currently working on. It is called a White Pupil Echelle Spectrograph and closely matches the designs used by professional exoplanet hunters. The first spectrograph covered 100 angstroms over 500 pixels, this new system covers 4000 angstroms using 40,000 pixels. It is many orders of magnitude more precise than its predecessor.

The picture below right is a low resolution spectrograph I built for Tenagra Observatories as part of our collaboration program on their 32" scope. Its main goal is to look at very faint stars and supernova.

White pupil echelle spectrograph layout.White pupil echelle spectrograph layout.

Tenagra Observatories low resolution spectrographTenagra Observatories low resolution spectrograph
I have a chapter in this book on constructing spectrographsI have a chapter in this book on constructing spectrographs
High resolution echelle spectrumHigh resolution echelle spectrum