SPECBUILDR
Custom optics · lens design

Write a build-ready custom lens spec — without being an optics expert.

You know what your product needs the lens to do. SpecBuildr asks a short set of plain-English questions and turns your answers into a complete optical specification a lens manufacturer can actually quote and build from.

Start your lens spec → Free · no account · ~5 minutes

The problem with speccing a lens

If optics isn't your field, the hard part isn't the design — it's knowing what to even specify. A machine shop will happily quote a bracket from a sketch. An optics vendor needs numbers most engineers have never had to name.

Send a vague request and you get one of two things back: a long list of clarifying questions, or a quote with so much margin baked in for the unknowns that it's useless. SpecBuildr closes that gap. It asks you the questions a good optical engineer would ask — in language you already understand — and translates your answers into the terms the shop expects.

How to specify a custom lens: what the spec needs

Specifying a custom lens comes down to six things a manufacturer needs to see. Here's what each one means in plain terms — you don't need to arrive knowing them, the interview draws them out of what you already know.

01 Focal length & aperture

How strongly the lens bends light, and how much light it collects (the f-number).

In plain terms: how far away things focus, and how bright the image is.

02 Wavelength band

The color or spectrum it must work at — visible, near-IR, a specific laser line.

In plain terms: what light is actually passing through it.

03 Material & coating

The glass or polymer type and any anti-reflection or protective coating.

In plain terms: what it's made of and how much light it wastes.

04 Size, mount & tolerances

Physical diameter, how it seats in your assembly, and how tight it has to be.

In plain terms: will it fit, and how fussy is it to make.

05 Image quality target

How sharp it needs to be (resolution / spot size) over the field you care about.

In plain terms: good enough for a sensor, or good enough for the eye.

06 Environment & volume

Temperature, shock, moisture — and whether it's one prototype or ten thousand parts.

In plain terms: where it lives and how many you need.

How it works

1
Answer a short interview
Describe your application in your own words. The tool asks follow-ups only where they matter and skips what it can safely infer.
2
It fills the gaps
Where you're unsure, it proposes a sensible default and explains the trade-off, so you're never blocked on a number you don't know.
3
Leave with a real spec
Download a clean, build-ready specification — reviewed for major physics and manufacturability violations — ready to send to lens vendors for a quote.

Built for the engineer, not the optician

  • Mechanical, EE, and systems engineers who own a product that happens to need a lens.
  • Hardware founders and PMs scoping an optical component for the first time.
  • Anyone getting quotes who wants to sound like they know what they're asking for — and actually does, by the end.

Questions

How do I specify a custom lens if I'm not an optics engineer?

You answer questions about your application in plain language, and the tool converts them into the parameters a lens shop needs — focal length, aperture, wavelength, material and coating, size and tolerances, and an image-quality target. It's written for competent engineers who aren't optics specialists: it asks about your product, not about ray-transfer matrices, and explains any term it introduces.

What do I actually get at the end?

A complete, downloadable lens specification: focal length and aperture, wavelength band, material and coating guidance, size and mounting, an image-quality target, and environmental and volume notes — formatted so an optics vendor can quote it directly.

Is the spec trustworthy?

It's generated from your answers and reviewed for major physics and manufacturability violations — it won't hand you something optically impossible. Treat it as a strong, vendor-ready starting point, not a substitute for a final review by whoever builds it.

How much does it cost?

The tool is free to use and needs no account. You keep the spec.

Ready to spec your lens?

Five minutes of plain questions. A build-ready specification at the end.

Start your lens spec →