How a Concave Mirror Solved a Automotive LiDAR Problem

For engineers working in Automotive LiDAR, the choice of a reflective surface is rarely an afterthought. Concave Mirror components sit at the heart of systems where…

For engineers working in Automotive LiDAR, the choice of a reflective surface is rarely an afterthought. Concave Mirror components sit at the heart of systems where measuring distance by timing reflected light pulses, and a small improvement in coating quality can change the result of an entire measurement or process.

A Concave Mirror is an optical component built so that reflection happens at the coated front face rather than through a substrate. With a dielectric or metallic on a BK7 or fused silica base, the part delivers > 99% reflectivity across laser line or visible while keeping the useful aperture clean and ghost-free.

Reflection on a first surface is straightforward physics: photons strike the coated face and are returned according to the law of reflection, angle in equals angle out. Because the coating sits on top, there is no second surface behind it to create a faint ghost image, which matters whenever contrast or measurement accuracy is at stake.

Most of the engineering in a Concave Mirror lives in its dielectric or metallic. The stack is designed for laser line or visible and delivers > 99%, and its environmental protection layer keeps the metal from tarnishing so the mirror keeps working year after year.

Substrate choice for a Concave Mirror is a trade between optical grade and budget. BK7 or fused silica is a common pick because it can be cut and polished to λ/10 flatness and a 20-10 surface, which is plenty for the reflection quality most Automotive LiDAR systems require.

A practical Concave Mirror datasheet reads: BK7 or fused silica substrate, λ/10 flatness, 20-10 quality, 1–10 mm thick, > 99% over laser line or visible. Those five lines settle most design reviews for Automotive LiDAR. See the standard size list for what we stock and what we cut to order.

Most Automotive LiDAR engineers reach for a Concave Mirror when they need measuring distance by timing reflected light pulses. The component's job is unglamorous but essential — keep the light on course and the loss low.

A typical situation

Consider a Automotive LiDAR builder who needed measuring distance by timing reflected light pulses. Starting from a stock part caused ghosting and loss. Switching to a made-to-print Concave Mirror — dielectric or metallic on BK7 or fused silica, flatness λ/10 — removed the ghost and recovered the lost light, turning an erratic bench setup into a repeatable instrument.

For Automotive LiDAR, do not over-specify. Choose the dielectric or metallic that covers laser line or visible at the angle you use, keep flatness at λ/10 unless the wavefront demands more, and you will have a Concave Mirror that is both capable and economical.

A Concave Mirror is tougher than it looks but softer than you think. Fingerprints on the dielectric or metallic are the usual cause of field failures, so edge-handling and capped storage pay off. A little discipline keeps > 99% where it belongs.

Our production of a Concave Mirror follows a simple, repeatable route: laser-cut the BK7 or fused silica to ±0.01 mm, smooth the edges, deposit the dielectric or metallic, and inspect to λ/10 / 20-10. Thickness options span 1–10 mm, and the same Hangzhou line that builds first-surface mirrors also runs windows, substrates and custom coatings.

A Concave Mirror is an optical component built so that reflection happens at the coated front face rather than through a substrate. With a dielectric or metallic on a BK7 or fused silica base, the part delivers > 99% reflectivity across laser line or visible while keeping the useful aperture clean and ghost-free.

The working principle is the law of reflection applied to a coated plane. Mount the Concave Mirror at 45° and a beam turns 90°; stack several and you fold a long path into a short box. That simplicity is why mirrors remain the fastest way to route light in Automotive LiDAR.

Mirrors reward careful handling. Hold a Concave Mirror by the edges, keep the coated face away from fingers and aerosols, and clean only with approved optics tissue and solvent when truly needed. Store it in its packaging, coated face protected, and it will hold > 99% for years.

The dielectric or metallic is where performance is won or lost. Deposited by vacuum processes, it is tuned so the reflected wave adds constructively across laser line or visible, reaching > 99%. Getting the layer thickness right is a precision task: a few nanometers off and the reflectivity curve shifts.

Durability is part of the spec, not an afterthought. For Automotive LiDAR the Concave Mirror should survive shipping, installation and the occasional wipe. The protective overcoat on the dielectric or metallic is what lets it do that without losing > 99% over time.

When you specify a Concave Mirror, the numbers that matter are flatness λ/10, finish 20-10, and the reflectance > 99% across laser line or visible. Thickness 1–10 mm is mostly about handling and mount compatibility, but it still belongs on the print. The specification table covers the common configurations.

The Concave Mirror is not exclusive to Automotive LiDAR. Universities, service centers and R&D groups use it wherever a beam must turn, which makes a flexible, customizable part a quiet workhorse across the optics world.

Our production of a Concave Mirror follows a simple, repeatable route: laser-cut the BK7 or fused silica to ±0.01 mm, smooth the edges, deposit the dielectric or metallic, and inspect to λ/10 / 20-10. Thickness options span 1–10 mm, and the same Hangzhou line that builds first-surface mirrors also runs windows, substrates and custom coatings.

Treat the dielectric or metallic as the asset it is. In Automotive LiDAR service, a Concave Mirror that is cleaned rarely and handled by the edge outlasts one that is wiped often. Less touching, more performance.

Mirrors reward careful handling. Hold a Concave Mirror by the edges, keep the coated face away from fingers and aerosols, and clean only with approved optics tissue and solvent when truly needed. Store it in its packaging, coated face protected, and it will hold > 99% for years.

Where measuring distance by timing reflected light pulses, a Concave Mirror earns its place by doing one job reliably: turning the beam without adding noise. In Automotive LiDAR that reliability is the difference between a prototype and a shippable product. More application examples are worth a look if the use case is close to yours.

Wrapping up

A Concave Mirror is a small part with an outsized effect on Automotive LiDAR. Get the dielectric or metallic, BK7 or fused silica and flatness right and the rest of the system behaves. If your drawing calls for something specific, the team at JYOPTO can cut and coat it to match — start from the specifications and standard sizes, then tell us the wavelength and angle.