1. Start with the camera function, not the lens catalog
Forward ADAS, surround view, rear view, DMS/OMS and CMS/DVR cameras solve different problems. A forward perception camera may prioritize useful contrast across the field and temperature. An AVM camera may prioritize projection consistency and peripheral performance. An in-cabin camera may require visible and NIR behavior to be designed together.
Write the function, camera location, target detection or viewing task, operating distance and expected scene conditions before comparing lens models.
- Camera function and installation position
- Objects or features that must be detected
- Day, night, HDR and NIR operating modes
- Working distance and scene depth
2. Match the lens to the exact image sensor
Sensor resolution is only one input. Optical format, active array, pixel size, cover glass, color filter array, microlens design and chief-ray-angle acceptance all influence the lens requirement. The same lens can produce different results on two sensors with the same nominal resolution.
Ask the lens supplier to evaluate the exact sensor and filter stack. Confirm image circle coverage, CRA compatibility and the spatial frequency used for MTF review.
- Sensor model and optical format
- Pixel size and active resolution
- Cover glass / IR-cut / RGB-IR stack
- CRA and image-circle requirement
3. Define FOV and distortion as one geometry problem
HFOV, VFOV and DFOV must be tied to the sensor active area and required scene coverage. For wide-angle systems, projection model and distortion curve can be more useful than a single distortion percentage. Calibration and image-stitching teams should be involved before the target curve is frozen.
A lens that reaches the requested diagonal FOV may still miss the required horizontal coverage or produce an unsuitable pixel distribution at the edge.
- Required HFOV / VFOV / DFOV
- Projection or distortion model
- Calibration and stitching constraints
- Acceptable edge pixel distribution
4. Specify image quality in measurable conditions
“High resolution” is not a complete requirement. Define the MTF frequency, field positions, wavelength range, f-number, object distance and temperature conditions. Include relative illumination, lateral color, flare and ghost targets where they affect perception or display quality.
The most useful specification connects optical measurements to the camera task. Center-only performance or room-temperature simulation cannot represent the entire production requirement.
- MTF frequency and field positions
- Nominal and temperature conditions
- Relative illumination and color consistency
- Ghost, flare and stray-light scenes
5. Close the loop with package, process and validation
TTL, BFL, mount, waterproof structure, adhesive, focus method and active-alignment strategy all affect final camera performance. Review tolerance stack-up and production controls before treating a design as ready.
A practical request for quotation should include program timing, sample stages, validation plan and expected annual volume. These inputs help determine whether a current platform, a modified platform or a new optical design is appropriate.
- Mechanical envelope, mount and sealing
- Focus / AA method and tolerance stack
- Reliability and camera-level validation
- Prototype, tooling, SOP and volume plan