Why Do Two 'Identical' Optical Components Have Very Different Prices?
Optical
9/23/20262 min read
Two optical lenses can have the same diameter, thickness, material, and shape.
So why can their prices be very different?
This is a common question when sourcing custom optical components.
The answer is simple:
The dimensions you see are only part of the specification.
1. The Material May Look the Same — But the Grade Can Be Different
“BK7” or “fused silica” alone may not tell the whole story.
Material grade, homogeneity, transmission requirements, and material certification can all affect the cost.
For some applications, a standard material may be sufficient.
For others, tighter optical requirements may be necessary.
2. Surface Quality Can Change the Cost
Two lenses may have the same diameter and focal length, but different surface-quality requirements.
For example:
60-40
versus
20-10
The tighter requirement requires more controlled polishing and inspection.
If the application does not need the tighter specification, over-specifying it may simply increase cost.
3. Coating Is More Than “AR Coated”
“AR coating” is not one universal specification.
The coating may need to match:
Operating wavelength
Wavelength range
Angle of incidence
Required transmission
Environmental conditions
A coating designed for one application may not be suitable for another.
4. Tolerances Matter
A drawing may specify:
Diameter tolerance
Thickness tolerance
Radius tolerance
Centration
Flatness
Wedge
Surface quality
The tighter these requirements become, the more difficult manufacturing and inspection can be.
A component with ±0.05 mm tolerance is not necessarily equivalent to one with ±0.01 mm tolerance—even if both look identical.
5. Inspection Requirements Also Add Cost
Sometimes the difference is not only in manufacturing.
It is also in how the component must be inspected and documented.
For example:
Standard inspection
Detailed inspection report
Material certificate
Coating test report
Individual test data
Special packaging requirements
For production equipment or regulated applications, these requirements may be important.
6. Quantity Changes the Economics
The same optical component can have very different unit costs at:
10 pcs
versus
1,000 pcs
Tooling, setup, coating batches, polishing efficiency, inspection, and production scheduling can all affect the final unit price.
So, Which Quote Is Actually Cheaper?
This is the important part.
A lower price does not automatically mean the supplier is offering the same product for less.
And a higher price does not automatically mean the product is better.
The first question should be:
“Are these two quotations actually based on the same specifications?”
Before comparing prices, check:
✔ Material
✔ Dimensions and tolerances
✔ Surface quality
✔ Flatness / wedge
✔ Coating specification
✔ Clear aperture
✔ Inspection requirements
✔ Quantity
✔ Packaging and delivery terms
The Takeaway
When comparing optical component quotations, don't compare the price alone.
Compare the specification behind the price.
Sometimes a supplier can reduce the cost without affecting performance simply by removing unnecessary specifications.
That's where a good optical supplier can help:
Not by making every specification tighter — but by matching the specification to the actual application.
At Positive Optics, we support custom optical components based on drawings, specifications, and application requirements, including lenses, windows, filters, prisms, and mirrors.