1. What is the PV value?

The PV value (peak-to-valley value) is a key indicator used to measure the surface flatness of optical components. It represents the vertical distance between the highest and lowest points on the surface. The PV value of quartz glass plates is less than 10 nanometres, equivalent to one ten-thousandth of the diameter of a human hair. This level of flatness meets the strict requirements of precision applications such as laser optics and aerospace lenses.

2. Why is the PV value important?

(1) Guarantee of optical performance

A smaller PV value means less wavefront distortion of light, which can significantly enhance the clarity of imaging and ensure that the optical system achieves high-quality image output.

(2) Improvement of energy efficiency

Low PV values can effectively reduce light scattering losses and improve the energy utilization rate of laser systems, which is particularly important in high-power laser applications.

(3) Enhancement of system stability

High flatness surfaces can reduce the risk of deformation caused by thermal stress and ensure that optical systems maintain stable performance in environments with temperature changes.

3. How to achieve a low PV value?

Modern manufacturing processes precisely control the PV value through three core technologies.

(1) Ion beam polishing technology

Atomic-level precision processing methods involve removing materials layer by layer through ion bombardment in order to achieve nanoscale surface correction.

(2) Detection and monitoring interference technology

Real-time monitoring is carried out using a laser interferometer to achieve sub-nanometer detection accuracy, providing accurate data support for process adjustment.

(3) Stress control process

Internal stress is eliminated through a special annealing process to ensure that quartz glass maintains dimensional stability during processing and use.

These advanced technologies are applied comprehensively to enable quartz glass plates to achieve a flatness standard of less than 10 nanometres, providing a reliable guarantee for precision optical systems.