Overview

Custom aperture etching uses photochemical machining to cut pinholes, slits, slots and multi-hole patterns into thin metal foil with sharp, burr-free edges. A photoresist mask carrying the aperture geometry is exposed and developed, and the unprotected metal dissolves in a matched etchant, so hole walls are formed by chemistry rather than by drilling or punching. Typical substrates are molybdenum, nickel and stainless steel 304/316L, supplied between 0.01 mm and 0.3 mm. Because no tool touches the foil, aperture edges stay knife-sharp, there is no deformation around the hole, and complex layouts — arrays, stepped slots, combined clear and opaque zones — all come from one film at no extra tooling cost.

Optical and sensor assemblies judge an aperture plate by three numbers: hole diameter or slot width, position accuracy, and edge condition. Custom aperture etching holds 0.05 mm holes and 0.03 mm slots with position within ±0.01 mm, and every part on the panel shares the same geometry because it is exposed together. Plates leave the process flat and clean, ready for blackening, gold flash or electroless nickel, then straight into laser heads, detector modules and sensor housings.

Parameter Window

• Available Materials: molybdenum, nickel, stainless steel 304/316L, titanium
• Material Thickness Range: 0.01–0.3 mm
• Tolerance: aperture size ±0.005 mm, position ±0.01 mm, profile ±0.01 mm
• Minimum Feature: 0.05 mm round aperture, 0.03 mm slot width on 0.05 mm foil
• Surface Options: black oxide, matte black coating, gold flash, electroless nickel, mirror polish
• Compliance: ISO 9001 process control, RoHS/REACH material traceability

Manufacturing Process / Workflow (8 Steps)

1. Aperture Drawing Review — Convert the hole and slot geometry to film data, check diameter, wall ratio and minimum web against foil thickness.
2. Material Selection — Choose molybdenum for thermal load, nickel for conductivity, or stainless 304/316L for corrosion resistance and stiffness.
3. Cleaning & Lamination — Degrease the foil and laminate dry film resist under controlled conditions so fine apertures develop cleanly.
4. UV Exposure — Expose the aperture pattern through high-resolution film with fiducials registered to the panel edge.
5. Development — Open the aperture areas and inspect under magnification for residual resist that would shrink hole size after etching.
6. Etching — Spray etch from one or both sides; double-side etching gives sharper knife-edges on thin foils and straighter walls.
7. Stripping & Surface Treatment — Remove resist, neutralize, then blacken or plate to control reflectance around the aperture.
8. Micro-Inspection & Packaging — Measure aperture size, position and edge condition on optical equipment, then pack each plate in its own protective sleeve.

Core Advantages

1. Knife-edge sharpness: Chemical etching leaves no burr or roll-over, so light meets a clean edge instead of a deformed rim that scatters the beam.
2. Geometry freedom: Pinholes, slits, arrays, stepped openings and combined clear/opaque zones all come from one film with no extra tooling.
3. Thin foil capability: Foils down to 0.01 mm can carry 0.05 mm apertures, which mechanical punching cannot hold without tearing.
4. Positional accuracy: Aperture centers hold ±0.01 mm to the plate edge, so sensor alignment survives assembly without rework.
5. Panel-level uniformity: All apertures on a sheet etch together, keeping size and edge condition identical across the batch.
6. Finish control: Blackening, gold flash and electroless nickel tune reflectance right at the aperture wall where stray light matters most.

Typical Applications

• Laser beam apertures: Pinhole plates that clean up beam profiles in laser processing and measurement heads.
• Sensor pinholes: Small defined openings in molybdenum or nickel that set the field of view for optical sensors.
• Optical slits: Narrow controlled slots for spectrometers, encoders and line-scan imaging modules.
• Beam-limiting masks: Multi-hole plates that sample or block parts of a beam path in metrology fixtures.
• Detector windows: Etched frames and openings that hold sensing elements with minimal stray-light leakage.
• Alignment targets: Aperture and cross patterns etched in stainless for calibrating optical assembly stations.

Design Notes & Process Considerations

1. Edge versus thickness: For the sharpest edge specify knife-edge profiles on foil at or below 0.05 mm; thicker stock gets slightly rounded walls by nature of the process.
2. Minimum web: Keep at least 0.1 mm of material between adjacent apertures, or the web thins during etch and can break in handling.
3. Position tolerance stacking: Reference aperture positions to one datum edge or hole, not to each other, so errors do not accumulate across the plate.
4. Reflectance at the wall: State whether aperture walls should be black, bright or plated; stray light behavior depends on this more than on the face finish.
5. Handling of thin foils: Specify protective sleeves and no-contact packing; a 0.01 mm foil plate dents from a fingernail and cannot be straightened.
6. Inspection method: Agree on the measurement setup — optical comparator or microscope with calibrated target — so incoming inspection matches the values custom aperture etching reports on the certificate.