Laser Planar Interferometer

The Laser Planar Interferometer (LPI-100), with its real-time dynamic measurement speed of up to 15 frames per second, is capable of real-time detection of the surface shape of planar optical elements within a 100mm aperture. The beam carrying the surface shape information of the measured element is diffracted through a specially encoded grating, which laterally shears the wavefront into four parts, forming a common-path shearing two-dimensional interference pattern with four wavefronts. By demodulating the two-dimensional interference, the surface shape information of the element can be obtained.

Item Specification:

Feature Of BOJIONG Laser Planar Interferometer

◆Up to 15 frames of real-time dynamic measurement

◆2nm RMS High phase resolution

◆Super high resolution of 262144 phase points

◆Can realize real-time dynamic detection, can achieve 15 frames/second dynamic detection

◆With independent intellectual property rights, cost-effective, simple adjustment, compact structure

◆Based on the principle of common channel self-interference, the equipment does not need a reference mirror, and has a strong resistance Interference capability, in the ordinary factory environment can also achieve accurate detection of flat surface

Application Of BOJIONG Laser Planar Interferometer

ThisBOJIONGLaser Planar Interferometer is equipped with FIS4 four wave interferometric sensors to detect the standard planar mirror shape, and the processing software outputs the PV value, RMS value, and POWER value of the surface of the tested component.

BOJIONG Laser Planar Interferometer Details

BOJIONG Planar Four-wave Dynamic Interferometer overall layout diagram

The functional modules of the BOJIONG Laser Planar Interferometer can be divided into an illumination light source module, a secondary beam expansion module, a carrier module, a spot focusing module for assisting in sample attitude adjustment, and an interferometric sensor module for sample surface shape detection.

The light source module of the system adopts a gas helium neon laser with a central wavelength of 632.8nm.

The secondary beam expansion module expands the beam size to 100mm, meeting the requirements for large-diameter detection.

The stage section is used to place planar optical components to be tested, such as flat crystals, single throw wafers, window chips, planar reflectors, etc. The loading stage is equipped with X and Y direction moving handwheels to control the movement of the sample stage, so that the equipment's emitted light spot completely covers the surface of the test sample. At the same time, two knobs are also installed on the stage to adjust the sample tilt posture. By adjusting these knobs, the test plane is made perpendicular to the optical axis.

The imaging system has a dual camera system. One of them uses an optical imaging camera to form a spot focusing module for assisting in sample posture adjustment. By observing the sample's return spot position in real time, the sample posture is adjusted to ensure measurement accuracy. The other path is equipped with FIS4 four wave interferometric sensor, forming an interferometric sensor module for sample surface shape detection. By recording common path interferometric fringes, real-time feedback of three-dimensional information on the surface of the test sample can be achieved. The dual camera system can work simultaneously.

Professional software module

◆Equipped with the "Laser Planar Interferometer" software, it can display and output real-time 3D images of the measured optical element plane, output PV values, RMS values, and POWER values of the measured surface.

◆At the same time, the software supports exporting raw data of measurement results, providing quantitative detection data support for various studies, and facilitating users to conduct data analysis and research in the future.