FluoroMax - Compact Spectrofluorometer

The Source

Starting with a xenon source that supplies prime UV performance, we mount the bulb vertically, since horizontal mounting leads to sagging of the arc that increases instability and decreases the useful life.

The xenon source is focused onto the entrance slit of the excitation monochromator with an elliptical mirror. Besides ensuring efficient collection, the reflective surface keeps all wavelengths focused on the slit, unlike lenses with chromatic aberrations that make them totally efficient only at one wavelength.

As an option an additional, software-selectable, xenon flash lamp can be fitted to enable phosphorescence studies.

The Slits

The slits themselves are bilaterally, continuously adjustable from the computer in units of bandpass or millimeters. This preserves maximum resolution and instant reproducibility.

The Excitation Monochromator

The excitation monochromator is an aspheric design which ensures that the image of the light diffracted by the grating fits through the slit. The gratings themselves are plane, blazed gratings that avoid the two major disadvantages of the more common concave holographic gratings: poor polarization performance and inadequate imaging during scans that throws away light. The unique wavelength drive scans the grating at speeds as high as 80 nm/s. The grating grooves are blazed to provide maximum light in the UV and visible region.

The Reference Detector

Before the excitation light reaches the sample, a photodiode reference detector monitors the intensity as a function of time and wavelength. The photodiode detector has a wider wavelength response than the older, traditional rhodamine-B quantum counter, and requires no maintenance.

The Sample Chamber

A spacious sample chamber is provided to allow the use of a long list of accessories for special samples, and encourages the user to utilize a variety of sample schemes.

The Emission Monochromator

All the outstanding features of the excitation monochromator are also incorporated into the emission monochromator. Gratings are blazed to provide maximum throughput in the visible region.

The Emission Detector

Emission detector electronics employ photon-counting for the ultimate in low-light-level detection. Photon-counting concentrates on signals that originate from fluorescence emission, ignoring smaller signals originating in the detector tube (PMT). The more common method of analog detection (used by lower performance fluorometers) simply adds noise and signal together, masking weak emissions.

The emission detector housing also contains an integral high-voltage supply which is factory set to provide the signal-to-noise ratio.

Computer Control

The entire control of the FluoroMax^®-4 originates in your PC with our FluorEssence™ software and is transmitted through a USB link. On start-up, the system automatically calibrates and presents itself for new experiments, or stored routines instantly called from memory.

Accessories

A wide variety of accessories are applications-oriented and most are interchangeable with the FluoroMax^®-4 system.