Laser-based particle analysis technology continuously monitors the size and optical properties of particles in a single air, which may be a better way to monitor air pollution.
In this new analytical method, particles in the air are captured by the optical force in a laser beam (3 W CW, 1064 nm wavelength) and propelled by the radiation pressure. The trapping power is sufficient to overcome the gravity acting on very small particles (such as PM2.5) and automatically align the particles with the hollow photonic crystal fiber (HC-PCF), which has a central core, thus making the LPo1 mode Can spread. The core is hollow and surrounded by a glass microstructure that confines light inside the fiber.
After alignment, the laser advances the particles into the fiber, causing laser light scattering inside the fiber and producing a detectable decrease in fiber transmission. Researchers have developed a new signal processing algorithm that retrieves useful information from particle scatter data in real time. After detection, the particles are only ejected from the fiber without degrading the device.