LiDAR Sensor Windows and Cover Optics

LiDAR can pass through glass, but performance depends on the glass composition, thickness, surface quality, angle of incidence, and the LiDAR wavelength. Glass can create reflection losses, ghost signals, attenuation, or distortion that affect range and signal quality. An appropriately selected substrate and anti-reflective coating can reduce unwanted reflections and improve transmission for the intended sensing band.

A LiDAR sensor window is a protective optical element placed in front of a transmitter, receiver, or complete sensor module. It protects internal components from handling and environmental exposure while allowing the required laser wavelengths to pass through. Its optical surface quality, material, shape, coatings, and mounting design must be considered together to limit reflection, scatter, distortion, and alignment concerns.

Anti-reflective coatings are designed to reduce reflectivity over selected wavelength ranges. For LiDAR cover optics, lower reflections can improve useful transmission and help control stray light that may interfere with received signals. The coating must be matched to the substrate, wavelength range, angle conditions, and environmental expectations. Apollo applies thin-film coating expertise to plastic and glass optical components.

Material selection depends on optical requirements, environmental exposure, mechanical design, and production volume. Apollo works with optical polymers including acrylic, styrene, Zeonex, Zeonor, Ultem, polycarbonate, and specialty materials, as well as metals for applicable optical components. Each material presents different tradeoffs involving transmission, birefringence, heat resistance, moisture resistance, chemical resistance, dimensional stability, and cost.

Yes. Single-point diamond turning can produce small quantities of custom optical prototypes before production molding. This capability supports the evaluation of optical form, material behavior, surface quality, mechanical fit, and system-level performance without immediately committing to high-volume tooling. Design verification, tolerance analysis, and metrology can further help assess whether the prototype meets defined requirements before scaling.

Verification can combine optical simulation, tolerance analysis, prototype evaluation, and in-house metrology. Apollo’s equipment supports measurement of critical mechanical and optical parameters, including dimensions, surface roughness, topography, surface figure, and optical retardation for polarization-critical components. The appropriate test plan should reflect the window’s design specifications, LiDAR wavelength, mounting conditions, and intended operating environment.

Polymer optics can be a practical choice when the selected material, optical design, coating process, and manufacturing method match the application requirements. Apollo’s capabilities include polymer injection molding, diamond turning, thin-film coatings for plastic components, and assembly. Materials can be evaluated for factors such as optical clarity, heat resistance, low birefringence, moisture resistance, chemical resistance, and production economics.

Tolerance analysis should begin during the design phase, before tooling or production decisions are finalized. It evaluates how manufacturing variation, alignment, mechanical interfaces, and optical surfaces may affect system performance. By coordinating optical and mechanical requirements with manufacturing capability early, teams can set realistic tolerances, reduce avoidable iteration, and improve the likelihood that production parts perform as intended.