A stock lens matrix assigns a quantity to each approved sphere-and-cylinder combination within one clearly defined product specification. It should also identify the cylinder notation, material, design, diameter, coating and unit of sale. A total quantity alone does not tell a supplier which combinations to ship or tell a warehouse how to receive them.
Key takeaways
- Define plus- or minus-cylinder notation before exchanging a matrix.
- Separate unavailable cells from zero-quantity cells.
- Make pieces, pairs and commercial units explicit.
Start with one specification per matrix
Use a separate matrix when a change of material, diameter, coating or design would create a different SKU. Putting everything into one sheet can hide important differences behind the same power label. Add a product specification reference and revision date above the grid.
Lensmeters can report cylinder using different sign conventions; Topcon lists plus, minus and mixed cylinder modes. Agree the notation before comparing measurements with an order. Prescription transposition and dispensing decisions should be handled by qualified optical staff.
Define the cells and their meaning
A spreadsheet should distinguish a combination that exists but is not ordered from a combination the supplier cannot provide. Empty cells are ambiguous. Use a documented convention and validate totals before sending the final file.
| Field | Example format | Why it matters |
|---|---|---|
| Sphere / cylinder | Signed values with agreed decimal precision | Avoids sign and rounding ambiguity |
| Quantity | Integer number of pieces | Prevents piece-versus-pair disputes |
| Availability | Available / unavailable / awaiting confirmation | Keeps exclusions visible |
| Specification | Material + design + diameter + coating revision | Identifies the actual product |
Check totals before you approve the order
For an illustrative arithmetic check, four approved combinations at 25 pieces each make 100 pieces. That does not automatically mean 50 matched prescription pairs. Decide whether the commercial unit means two identical stock blanks, a prescribed right-and-left pair, or another agreed pack configuration.
Ask the supplier to return the same matrix with confirmed quantities and substitutions highlighted. Compare the total, every changed cell and the specification header. A correct grand total can still conceal missing high-demand combinations and excess slow-moving stock.
- Confirm all sphere and cylinder signs.
- Review boundary combinations and unavailable cells.
- Lock the approved revision before production.
- Attach the matrix reference to the invoice and packing list.
Connect the matrix to warehouse receiving
Give each confirmed combination a stable internal item code. Labels and packing lists should allow receiving staff to reconcile cartons against the approved cells without reinterpreting free-text descriptions.
Keep the requested matrix, supplier confirmation and actual receipt as separate records. That makes a short shipment visible and supports a more accurate reorder. Do not overwrite the original quantities with what arrived, because that removes evidence of the variance.
Buyer questions
Frequently asked questions
Should plus and minus cylinder share a sheet?
Prefer one agreed convention per matrix. If both are used, separate and label them clearly and have optical staff validate any conversions.
Does a zero mean the product is unavailable?
Only if the sheet explicitly defines it that way. Separate zero ordered quantity from unavailable combinations.
Should axis appear in a stock blank matrix?
The requirement depends on the supply stage. For uncut stock blanks, confirm axis markings and identification requirements; for finished prescription work, the full job specification is needed.
Further reading
These external references provide background context. Product availability and performance claims must still be confirmed for the exact item being purchased.