Figure 2
From: Improvement of the signal to noise ratio for fluorescent imaging in microfluidic chips
(A) Diagram of the light measurement through the rotated filter showing LED with a principal wavelength of 475 nm (LED 475 nm) connected to the excitation filter (blue) perpendicular to the light via optical fiber and attenuator (AT), emission filter (green) on a rotating platform, and either a photomultiplier tube (PMT) as light detector (shown here) or spectrum analyzer (not shown here). (B) Schematically showing the green filter rotation and its influence on (C) measured detected power on the PMT and (D–F) detected spectra for four different angles of the emission filter position.
