VR/AR Lens Thickness Measurement

As the demand for lightweight and high-performance VR/AR headsets grows, so does the need for accurate inspection technology. One key factor impacting both user comfort and device performance is the lens thickness.

In this article, we explore how Hypersen’s HPS-LCX1000 3D Line Confocal Sensor is used for non-contact thickness measurement of transparent curved lenses, helping manufacturers ensure quality while reducing weight.

One of the most challenging materials to inspect visually is black rubber.

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Why Lens Thickness Matters in VR/AR Devices

Next-generation headsets like Apple’s Vision Pro and devices from Meta, Sony, HTC, and others rely on ultra-thin and lightweight lenses. These lenses are often made from transparent and highly curved materials, making them difficult to measure using traditional inspection tools.

Lens thickness affects:

  • Visual clarity and projection angle

  • Device weight

  • User comfort, especially at the nose and forehead areas

For these reasons, accurate and reliable thickness measurement has become a standard quality control step in the production of VR/AR devices.

Application Test Overview

Objective

Measure the thickness of transparent, curved VR/AR lenses with high accuracy.

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Sensor Used

Hypersen HPS-LCX1000

  • Non-contact 3D Line Confocal Sensor

  • Z-axis repeatability: 0.1 μm

  • X-axis resolution: 1.1 μm

  • Ideal for transparent, mirror-finished, and high-reflection surfaces

Test Procedure

The lens sample was scanned using the HPS-LCX1000. The sensor collected high-resolution 3D profile data across the curved transparent surface in one pass.

After capturing the full surface profile, the software identified two reflective peaks, corresponding to the top and bottom surfaces of the lens. Using the known refractive index of the lens material, the system calculated the precise thickness.

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Result

  • Measured lens thickness: 1058.4 μm

This result demonstrates the sensor’s ability to measure challenging optical components with micron-level precision, even on complex shapes and materials.

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Why 3D Line Confocal for VR/AR Lens Inspection?

Traditional sensors often struggle with:

  • Transparent surfaces

  • Curved shapes

  • Highly reflective coatings

The HPS-LCX1000 overcomes these challenges by:

  • Using confocal chromatic dispersion to separate light reflected from different depths

  • Generating real-time 2D and 3D profiles

  • Operating independently of surface reflectivity

Applications Beyond VR/AR

This sensing technology is widely used for:

  • Optical components inspection

  • Smartphone camera modules

  • Medical lenses

  • Precision glass and sapphire products

  • Thin film and coating thickness control

About the Sensor

HPS-LC Series

  • Non-contact, optical 3D metrology

  • High-speed CMOS line scanning

  • Compatible with nearly all materials: glass, metal, rubber, plastic, ceramic

  • Suitable for inline and offline quality control