5. Optical System
74
Instructions for Use for
infinite® 200
No. 30017581 Rev. No. 1.4
2008-07
5.2.2
Fluorescence Optics Top
Flash light enters the optical system by being focused through an orifice. This
opening acts as a color specific light source. A semi-transparent mirror (beam
splitter) reflects 50% of the light towards the microplate. The objective lens
system focuses the light into the sample.
Fluorescence Emission is measured from above the well. Fluorescence light is
collected by the objective, directed through the 50% mirror, and focused through
the exit orifice for detection.
Objective Lens System
The objective is designed to collect as much of the fluorescent light from a well
and focus it through the exit orifice to the detection system.
The objective lenses are made from fused silica. This material provides high UV
transmission and is virtually void of auto-fluorescence.
5.2.3
Fluorescence Optics Bottom
Flash light enters the optical system by being focused through an orifice. This
opening acts as a color specific light source. The excitation bottom fiber guides
the light to the bottom measurement head, which consists of an elliptical mirror
focusing the light through the bottom of the microplate into the well. The emitted
light is focused onto the excitation bottom fiber, which guides the light over a
mirror through the emission filter into the fluorescence detection system.
5.2.4
Fluorescence Detection
Emission Filter
The emission filter discriminates scatter of excitation light and unspecific
fluorescence. The emission filter is part of a filter set containing excitation filter,
emission filter and a 50 % mirror.
PMT Detector
A photomultiplier tube (PMT) is used for the detection of such low light levels as
involved with fluorescence. For details see 5.1.3 Fluorescence Intensity
Detection.
