Custom Infrared Dome Prototypes: From Sample Validation to Mass Production
Custom Infrared Dome Prototypes: How to Move from Samples to Production
Ordering a custom infrared dome prototype is an important step in developing an optical assembly. However, receiving a sample is only the beginning of validation.
Before placing a production order, the buyer and manufacturer need a shared understanding of what the prototype must demonstrate, how it will be tested and which requirements will control future deliveries.
A structured evaluation helps identify design changes early and creates a clearer basis for repeat orders.
1. Give the Prototype a Defined Purpose
A prototype order should answer specific engineering questions.
An early sample may be intended to verify mechanical fit. A later sample may need to demonstrate spectral transmission, imaging performance or compatibility with the intended operating environment.
These stages should be distinguished clearly.
| Prototype purpose | Main question |
|---|---|
| Mechanical evaluation | Does the component fit the housing correctly? |
| Optical evaluation | Does it meet the defined optical requirements? |
| Assembly evaluation | Can it be installed and retained as intended? |
| Environmental evaluation | Does the assembly meet the specified exposure conditions? |
| Production qualification | Can the agreed design and process support repeat orders? |
A sample approved for fit should not automatically be treated as approved for optical or environmental performance.
2. Establish the Sample Configuration
Before manufacturing begins, identify the configuration being evaluated.
Record the drawing revision, material grade, coating specification, quantities and any agreed deviations. If the sample differs from the intended production component, explain how that difference affects the evaluation.
For example, an uncoated sample may help assess fit and geometry, but it cannot establish the transmission of the final coated component.
A practical sample record should include:
- Part number and drawing revision.
- Material and grade.
- Surface and coating requirements.
- Applicable dimensional and optical tolerances.
- Approved deviations.
- Required inspection documents.
- Sample or batch identification.
This record makes test results easier to interpret and prevents uncertainty during repeat orders.
3. Inspect the Samples Before Assembly
Check the samples and accompanying documents before installing them.
Verify identification, quantity and the reported configuration. Inspect for shipping damage and review the agreed dimensional and optical inspection results.
Where incoming measurements are required, use the agreed methods and handling procedures. Protect the optical surfaces during unpacking, measurement and storage.
If a discrepancy is found, document it before assembly. Photographs and clearly identified measurement results can help the manufacturer investigate the issue.
4. Evaluate Mechanical Fit in the Actual Housing
Mechanical evaluation should use the intended housing or a representative fixture.
Check the seating position, retaining arrangement, clearances and seal interface. Confirm that mounting hardware does not contact unintended optical areas.
| Area | What to check |
|---|---|
| Seating interface | The dome locates on the intended contact surfaces |
| Retention | The retaining arrangement assembles as designed |
| Clearance | Adequate space exists around the component |
| Clear aperture | The housing does not obstruct required optical paths |
| Sealing interface | Seals are positioned and supported as intended |
| Assembly procedure | Installation can be performed consistently |
Record assembly conditions where they affect the result. A successful installation should be reproducible rather than dependent on undocumented adjustments.
5. Review Spectral Performance Against the Agreed Limits
Transmission evaluation should follow the specification used for the order.
Confirm the wavelength band, acceptance metric, measurement geometry and whether the results apply to the finished dome or a witness sample.
Do not substitute a general material transmission curve for the agreed finished-component requirement.
For broadband applications, review the complete operating band. If the specification defines minimum transmission, an average value alone is insufficient to establish compliance.
If testing uses a witness sample, document its relationship to the coating batch and identify which requirements still need verification on the dome.
6. Test Imaging Performance in the Intended Arrangement
For an imaging application, evaluate the dome with the relevant camera, lens and mounting position.
Testing should cover the useful field of view rather than only the center of the image. If the optical assembly moves, include the required operating positions.
The evaluation plan may address image quality, focus behavior, obstruction or other system requirements. Use acceptance criteria established by the system designer.
A dome can meet individual drawing requirements while the complete system still needs adjustment. Keeping component inspection and system evaluation separate helps identify where a change is needed.
7. Evaluate Coating and Environmental Requirements Deliberately
Environmental testing should reflect the intended service conditions.
Specify the procedure, test configuration, sample quantity and pass criteria before testing. Identify whether the evaluation applies to the dome alone or the complete mounted assembly.
Depending on the application, the plan may include cleaning compatibility, temperature exposure, moisture or other defined conditions.
Tests that may damage a component should be planned separately from samples needed for further optical evaluation. Agree on sample allocation before placing the prototype order.
8. Classify Findings Before Changing the Design
When a sample does not meet expectations, first establish what happened.
A useful review distinguishes among:
- A component that does not meet the agreed specification.
- A component that meets the specification but does not satisfy the system’s needs.
- An assembly or handling issue.
- An evaluation method that differs from the agreed method.
- A requirement that was not defined before manufacturing.
These situations call for different actions.
For a dimensional concern, provide the measured location, datum and method. For an optical concern, include the test setup and conditions. For an assembly issue, share the relevant housing details and observations.
Specific evidence supports a more effective review than a general statement that the sample “does not work.”
9. Update the Documents After Prototype Approval
Prototype approval should identify exactly what has been accepted.
If testing leads to changes, update the drawing and related specifications before the next order. Avoid relying on email instructions scattered across several conversations.
| Document or record | Purpose |
|---|---|
| Approved drawing | Controls geometry and applicable tolerances |
| Material specification | Identifies the required substrate and grade |
| Coating specification | Defines optical and applicable durability requirements |
| Inspection plan | Establishes verification methods and acceptance criteria |
| Approved deviations | Records any accepted exceptions |
| Packaging requirements | Defines protection, identification and delivery condition |
If a reference sample is retained, identify its role. It should support the written requirements rather than create a second, conflicting acceptance standard.
10. Confirm the Production Order Scope
Before moving to production, confirm quantities, delivery requirements and documentation.
Ask the manufacturer to review the final configuration and identify any changes in tooling, inspection or process arrangements needed for the production quantity.
Where changes could affect performance, agree on the required notification and approval process.
A successful prototype provides useful evidence, but repeatability depends on a controlled specification and an agreed manufacturing and inspection approach.
A Practical Prototype Approval Checklist
Before releasing a production order, confirm:
- The approved sample configuration is identified.
- Mechanical fit has been evaluated.
- Required optical results have been reviewed.
- Applicable assembly and environmental evaluations are complete.
- Findings and corrective actions are closed.
- Drawings and specifications reflect the final design.
- Production inspection and packaging requirements are agreed.
- Any remaining limitations or exceptions are documented.
The objective is a clear decision: what has been demonstrated, what remains open and what the manufacturer must deliver next.
Discuss Your Infrared Dome Prototype with Felix Glass
Send Felix Glass your drawing, operating wavelengths, prototype quantities and evaluation goals.
If the design is still being developed, identify which questions the first samples should answer. This helps define a useful prototype scope and a clearer path toward production.
Contact: James Fu
Company: FELIX OPTICAL GLASS
Email: james@felixglass.com
Website: https://www.felixglass.com/
