June 13, 2021  ·  Concave Mirror

How to Select a Concave Mirror for Defense & Aerospace

Every Defense & Aerospace system eventually meets the same question: where does the light go, and how much of it survives the turn? A well-specified Concave Mirror…

Every Defense & Aerospace system eventually meets the same question: where does the light go, and how much of it survives the turn? A well-specified Concave Mirror answers both, which is why it earns a place on the bill of materials long before the enclosure is drawn.

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.

Coating a Concave Mirror means laying down a dielectric or metallic whose optical thickness is controlled to a fraction of a wavelength. Done well, the part holds > 99% over laser line or visible; done carelessly, it drifts and the system loses light it cannot afford to lose.

A Concave Mirror starts as a BK7 or fused silica blank. We hold it to λ/10 flatness and 20-10 surface quality, then apply the dielectric or metallic. The substrate never sees the beam directly, but its figure sets the limit on how straight the reflected wavefront stays.

Typical specs worth putting on a drawing: surface flatness λ/10, surface quality 20-10 (scratch-dig), substrate BK7 or fused silica, thickness 1–10 mm, and reflectivity > 99% over laser line or visible. Stating these up front saves rounds of sampling later. Our full technical specifications and standard sizes list the tolerances we hold routinely.

Where rugged, repeatable optics for harsh environments, a Concave Mirror earns its place by doing one job reliably: turning the beam without adding noise. In Defense & Aerospace 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.

For Defense & Aerospace, 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 short checklist covers most Defense & Aerospace cases: what band (laser line or visible)? at what angle? how much loss is allowed (> 99%)? then pick dielectric or metallic on BK7 or fused silica at 1–10 mm. Getting these four right avoids the most common rework — the application notes show how each sector resolves them.

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 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.

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.

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.

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 Defense & Aerospace. See the standard size list for what we stock and what we cut to order.

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.

Where rugged, repeatable optics for harsh environments, a Concave Mirror earns its place by doing one job reliably: turning the beam without adding noise. In Defense & Aerospace 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.

How the part is checked

Before a Concave Mirror leaves the line it is inspected for flatness (λ/10), finish (20-10) and reflectance (> 99% over laser line or visible). A simple 45° visual check reveals coating defects, and a flatness test confirms the wavefront stays within tolerance — the same discipline JYOPTO applies across its optical glass, vacuum-coating and precision cold-processing since 2020.

At JYOPTO we make Concave Mirror parts by cutting BK7 or fused silica with laser accuracy of ±0.01 mm, then applying the dielectric or metallic under vacuum. Standard blanks run 1–10 mm thick, edges are smoothed for safe handling, and every shipped mirror meets λ/10 flatness with a 20-10 surface — the same disciplines we apply across our optical glass, vacuum-coating and precision cold-processing lines since 2020.

One term worth knowing

"Reflectivity" on a Concave Mirror is the fraction of incident light returned by the dielectric or metallic. Quoting > 99% without the band (laser line or visible) is meaningless, because the same coating can be excellent at one wavelength and poor at another — always pair the number with the range.

At JYOPTO we make Concave Mirror parts by cutting BK7 or fused silica with laser accuracy of ±0.01 mm, then applying the dielectric or metallic under vacuum. Standard blanks run 1–10 mm thick, edges are smoothed for safe handling, and every shipped mirror meets λ/10 flatness with a 20-10 surface — the same disciplines we apply across our optical glass, vacuum-coating and precision cold-processing lines since 2020.

Wrapping up

A Concave Mirror is a small part with an outsized effect on Defense & Aerospace. 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.

Talk to JYOPTO about your mirror needs

Custom sizes, coatings and substrates — cut to ±0.01 mm, shipped worldwide.