MANUFACTURING / JAPAN SOURCING
Glass and quartz parts: what belongs beside the outline drawing?
A clear window with the right diameter may still leave its optical, thermal and mounting requirements undefined. State what the finished part must do, then ask for a material and processing proposal tied to those conditions.
Describe the job of the window
Consider a flat window in an optical inspection head near a heated process. The drawing gives the outer diameter and thickness, but the enquiry only says “quartz, transparent”. It leaves the supplier to guess what light must pass through, what surface is useful and how the part will be mounted.
Send the wavelength or band, required transmission and its evaluation conditions, useful optical area, temperature history, exposure and mounting concept. If pressure, vacuum or safety containment is involved, identify that duty explicitly for the responsible design team. The optical-material name does not establish structural suitability.
- 1Geometry: outside edge, thickness and edge condition
- 2Optical area: identify the region and the light passing through it
- 3Installation: identify support, contact and thermal exposure
Front and side views are schematic. The inner circle marks an area to specify, not a standard aperture ratio. Supports do not represent a validated mount or pressure boundary.
Ask which grade supports the intended use
AGC lists several synthetic fused-silica grades with different application descriptions.[1] An offer reading only “quartz” therefore needs a more specific material reference and supporting information. Ask the supplier to identify the manufacturer/grade and proposed alternatives, rather than approving a familiar family name.
For transmission data, retain the wavelength range, specimen thickness, surface/coating state and measurement basis. LAYERTEC’s material page labels the thickness of its transmission-spectrum example and discusses absorption differences.[2] Use data for the offered material and finished configuration; a general curve is not an acceptance report for this window.
Keep fit, surface quality and optical performance separate
State which faces require polishing, any coating, the clear aperture, edge/chamfer requirements and the relevant drawing tolerances. Clarify which requirements apply before and after coating or other finishing. Do not call every surface “optical quality” without defining the required attributes.
LAYERTEC distinguishes dimensional tolerances, surface form, transmitted wavefront and surface imperfections in its specification guide.[3] Ask the optical designer which of these matter for the inspection task and how they will be evaluated. A scratch/dig label or surface-flatness number should not silently stand in for the entire functional requirement.
| Requirement | Specify or mark unknown | Evidence to agree |
|---|---|---|
| Material | Specify or mark unknownManufacturer/grade, part revision and permitted alternatives | Evidence to agreeApplicable material and lot records |
| Light | Specify or mark unknownWavelength/band, transmission, angle and useful area | Evidence to agreeMethod and finished-part state for optical evaluation |
| Surfaces and edge | Specify or mark unknownPolished faces, coating, form/defect criteria and edge finish | Evidence to agreeDrawing details and measurement/inspection conditions |
| Heat and contact | Specify or mark unknownTemperature/time/cycles, contact media and mounting | Evidence to agreeApplication assessment and any required assembly trial |
| Delivery | Specify or mark unknownCleaning, handling, protection and quantity | Evidence to agreeAcceptance records, packing and handover state |
Make thermal and mounting assumptions visible
For the heated inspection head, give normal and transient temperatures, heating/cooling timing and where the part contacts its holder. Also identify cleaning fluids, deposits or other contact media. Ask which information is still needed to assess the proposed material, coating and mounting arrangement.
Do not use a catalogue softening point as the allowed operating temperature of an assembled window. The responsible team should define applicable limits and evaluation conditions for the actual combination. If a trial is needed, identify its purpose, part state and decision criteria before ordering samples.
Compare the delivered state and the remaining decisions
Ask each supplier to distinguish material blank, cut/ground part, polished/coated part and cleaned/packed delivery. Retain proposed deviations, measurement reports, sample scope and the person who can accept changes. A low price for a blank is not directly comparable with a finished optical component.
Keep the material and drawing revisions, accepted references and open technical questions together. HAM can help organize the enquiry and supplier responses; final optical, thermal and mechanical design decisions remain with the responsible specialists.
Questions to send your supplier
Open supplier questions
Product: flat window in an optical inspection head Drawing/revision, dimensions, edge and mounting concept: Material/grade known or requested proposal: Wavelength/band, transmission target, angle and clear aperture: Polished faces, coating, surface-form and defect requirements: Temperature history, heating/cooling, contact media and cleaning: Pressure/vacuum/containment duty, if present: Please identify data and evaluations for the proposed finished configuration. Separate blank, processing, coating, cleaning/packing, reports and sample costs. List deviations, unknowns, acceptance criteria and decision owners. Quantity, destination and timing:
Sources
- AGC — Synthetic fused silica glass AQ series
Grade/application and polished-substrate sections. Reference property values are not design limits or guaranteed acceptance criteria for another part.
- LAYERTEC — Substrate materials
Fused-silica transmission spectrum is labelled by thickness; material/process and absorption distinctions inform questions, not a chosen grade or universal transmission range.
- LAYERTEC — How to specify substrates
Specification categories and distinctions between size, surface form, transmitted wavefront and imperfections. Numerical examples, tolerances and simplified standard interpretations are not adopted.