FIS4-HR high-resolution wavefront sensor - the "precision ruler" for industrial optical detection

The quality of an optical lens, a precision window, and a set of imaging lenses often depends on the nanoscale surface undulations. How to quickly and stably detect these small deformations on site in the workshop? Today, let's take a look at how the FIS4 series wavefront sensor enables high-precision interferometry to move out of the laboratory and onto the production line.

Why is wavefront detection on the workshop site so difficult?

In optical component manufacturing, lens assembly, and window quality inspection, wavefront distortion directly determines the imaging quality and performance of the final product. However, traditional detection methods have long faced three major obstacles:

❌   Dependent on reference mirror: Taylor Green and Fizeau interferometers require high-precision reference surfaces, and the surface shape error of the reference mirror itself will be superimposed on the measurement results.

❌   Strict environmental requirements: It must be placed on a vibration isolation optical platform and maintained at a constant temperature and humidity, making it impossible to use in factory workshops.

❌   Adjustment is cumbersome and slow: it requires phase shifting and multi-step alignment, making it impossible to achieve online real-time detection.

For industrial scenarios with white light and LED lighting, such as distortion of car window glass, optical flatness, and surface roughness, traditional methods are both expensive and impractical.

FIS4-HR: No need for a reference mirror, not afraid of vibration, plug and play testing

The FIS4-HR high-resolution wavefront sensor is based on the principle of four wave transverse shear interferometry and uses a domestically developed random coding hybrid grating (REHG) to achieve self interference of a single beam of light. Simply put, the wavefront to be measured is split into two beams in the x and y directions using a specially designed digital grating, resulting in stable two-dimensional grid interference fringes at the intersection of the four beams. By demodulating the fringes, wavefront information such as PV and RMS can be obtained.

Parameter List:

Compared to micro lens array Hartmann sensors, it has more high-resolution phase points, wider adaptive band range, larger dynamic range, and better cost-effectiveness.

Three major scenarios covering the core requirements of industrial optical testing

Scenario 1: Optical Plane/Spherical Surface Shape Measurement

Real time detection of optical component surfaces, outputting three-dimensional contour maps, contour maps, and PV/RMS values. No need to transport to the laboratory, final inspection can be completed in the assembly workshop.

Scenario 2: Optical Window Distortion Detection

Small distortions in glass components such as industrial grade high-definition monitoring, vehicle mounted lenses, and infrared windows can cause imaging blur or geometric distortion. FIS4-HR quickly captures changes in the transmission wavefront, helping the production line to promptly eliminate defective products.

Scenario 3: Surface roughness and micro contour

Paired with a microscope objective lens, the FIS4-HR transforms into a white light profilometer, capable of measuring the roughness, step height, and groove depth of precision machined surfaces. Non contact, non damaging sample, ready to use after testing.

Domestic self-developed, speak with strength

The FIS4 series wavefront sensor is developed by a research and development team led by Professor Yang Yongying from Zhejiang University, with complete independent intellectual property rights.

✅  Domestic self-developed - the core grating design, processing, and algorithm are all independently controllable, with no export control risks.

✅  No need for vibration isolation - extremely strong anti vibration performance, suitable for high-precision testing in on-site and factory environments.

✅  Real time output -10 Hz full resolution 3D result display, dynamically observing wavefront changes.

✅  Foolish operation - equipped with professional software, one click acquisition, automatic demodulation, no need for phase shifting process.

✅  Lightweight and portable - plug and play, can be integrated into optical systems or handheld devices, flexible deployment.