This paper describes a laser-induced fluorescence (LIF) detection system for imaging proteins separated in a microfluidic device. The diameter of a laser beam is first increased through a beam expander, and subsequently focused into a line using a cylindrical lens. The resultant laser line is used to image an entire capillary or channel in which protein separation took place. The fluorescence emission is collected with a cooled, scientific grade charge-coupled device (CCD) camera. The detection limit was determined using a series of concentrations of fluorescein solutions. The temporal and spatial effects of photobleaching from laser irradiation were analyzed and the parameters to reduce the effect of photobleaching are discussed. We used the imaging system to demonstrate rapid analysis of proteins using isoelectric focusing.
A pushbroom sensor motion control system was developed for use in conjunction with a pulsed laser fan beam, streak tube camera, and a high speed low light level camera . The LIDAR and camera control system was tested to study the influence of water waves upon active-passive remote sensing systems and associated models that require pushbroom sensor motion. A pulsed laser fan beam signal at 532 nm was recorded using a streak tube camera and a (high speed, low light level, high quantum efficiency) digital CCD camera. Tests were conducted in 3 different water tanks, including 2 tanks with water waves (the longest wave tank or channel is 60 m long). Capillary waves, ~1 cm wavelength) were generated using an acoustic wave source generator. Streak tube camera and CCD images were collected in conjunction with a 532 nm pico-second short pulse laser. Images collected demonstrate the pulse stretching around submerged water
targets as well as the ability to discriminate water depth of submerged targets in shallow water types. In turbid water, the
pulsed layer backscatter structure showed a nearly random return as a function of depth if the signal was attenuated before reaching the bottom of the water column. The data collected indicated the motion control testing system can accommodate a variety of cameras and instruments in the lab and in the outdoor water wave channel. Data from these camera systems are being used to help validate analytical and Monte Carlo models of the water surface structure, and the
underwater light field structure (pulse stretching) as well as to validate other LIDAR applications used in bathymetric and hydrographic surveys of coastal waters and marine inlets for physical and biological (submerged vegetation) surveys.