Lumencor’s proprietary light engines are excitation subsystems. They include:
- a maximum of six light sources
- mirrors to direct the light and filters to define the bandpass
- an adapter to efficiently couple the light to a bioanalytical instrument
The optics and mechanics of coupling are optimized for a fluorescence microscope, high content screener, gene expression chip reader or for a customized tool designed to meet an individual need. All these elements combined constitute a light engine. They are considered in each design and included in the purchase price.
Lumencor’s technology incorporates the use of a variety of solid state sources in one optical train. Any one light engine can embody as many as three types of sources: LED, light pipe and laser. Lumencor employs these sources in customized designs to meet the wide array of spectral and power demands on the part of the end user. This flexibility means optical designs can readily be tailored to provide outputs from 370 nm violet light to 900 nm NIR. Lasers are employed only as needed or specified by the user. Laser speckle patterns are eliminated.
Unlike other solid state sources, Lumencor’s excitation subsystem includes a relatively broadly emitting light pipe for the green and yellow outputs. In contrast to the notorious “green gap” that plagues LED based technologies with low power, Lumencor’s highest power outputs reside in the yellow/green regions of the spectrum. Moreover NIR outputs are now available in place of the teal or red sources.
Light engines may be configured multiple ways: in fixed designs the bandpass filters are internal to the box and not accessible by the customer. As few as one and as many as six sources may be included in the design and their outputs are tailored and fixed by the filter selection. A filter switcher may be implemented in front of the green/yellow source to enable two output bands from this powerful source. All sources are serially operable; simultaneous operation at maximum power requires the purchase of an optional high power supply.
SPECTRAX light engines house six light sources. Their filters reside in user exchangeable holders. This model has all the flexibility of a filter wheel with no moving parts besides the cooling fan. SPECTRAX light engines ship with a higher power supply to enable simultaneous operation of all sources at maximum power.
Filters selection is critical to maximize the output power of the light engine and minimize bleed through of excitation light into emission bands. Lumencor’s staff is trained to guide customers in this selection.
Filter optimization is based on careful consideration of several factors:
- the fluorophores’ absorption, emission and Stokes shifts
- the overlap of the fluorophores’ absorption spectra with light engine excitation
- the optimal spectral output of each light engine source
- the use of single pass or multipass dichroic and emission filters for detection
- any preference on the part of the customer for filter manufacturer
Lumencor supports the use of numerous bandpass filters in the various light engine models and routinely works with coating houses to produce custom bandpass filters as the application and customer require.