5 results about "Cylindrical lens" patented technology

The present invention relates to a flow cytometer, comprising a light source, a light beam shaping module for collimating and converging a light beam emitted from the light source so that the light beam irradiates samples to be detected, a sample generation unit, which comprises a gas-liquid transmission controlling module and a flow chamber that are interconnected, and a signal processing unit, for collecting, photoelectrically converting and analyzing the scattered beam emitted from the flow chamber. The light beam shaping module comprises a first cylindrical lens and a second cylindrical lens for respectively converging the light beams in two directions. In the present invention, the spot converged at the cell-interrogation zone of the flow chamber is flattened to avoid instability of the fluid which in turn leads to instability of the excited optical signal, and consequently the stability and reliability of the system are improved.

Provided is a method for preparing a two-dimensional metallic photonic crystal structure in large area through femtosecond laser direct writing. The invention provides a method and experiment device for preparing the periodically-distributed two-dimensional photonic crystal structure with the feature size being the sub-micron dimension in one step in the large area by focusing identical-wavelength double-pulse femtosecond laser on the surface of metal through a plano-convex cylindrical lens, and the identical-wavelength double-pulse femtosecond laser is obtained based on the spectrophotometry of birefringent crystals and has the features of collinear transmission, cross polarization and picosecond time delay. Two-dimensional periodic structure patterns can be effectively regulated and controlled by changing the energy and the number of pulses of input laser, the thicknesses and the azimuth angles of the birefringent crystals and the like. Through the combined design of different linear polarization directions and the variable time delay feature of two femtosecond laser pulses and focusing of the cylindrical lens, preparation of the two-dimensional metallic photonic crystal structure within the large area is achieved conveniently and quickly. The novel preparation method adopting the double-pulse femtosecond laser with cross polarization and variable time delay has potential important applications in the field of material micro-nano processing and preparation.

The invention discloses a device and method for detecting the optical detector working point of a particle detector. The device comprises a laser, an external modulation device, a cylindrical lens group, a sample cell, a focusing lens and an optical detector which are distributed according to preset positions, wherein the external modulation device is used to generate a detection signal and load the detection signal on the laser beam sent by the laser; and the device also comprises an oscilloscope and a processing circuit, wherein the optical detector is connected with the oscilloscope and the processing circuit through signal wires respectively to display the detection signal from the external modulation device on the oscilloscope and process the detection signal in the processing circuit. By using the device and method of the invention, the optical detector can work in a linear work area and the particle detection can be performed more accurately.