Description
A grooved light guide rod is a fused quartz rod with one or more channels machined into its outer surface. The groove is the independent purchasing feature: it positions fibers or components while the rod body provides the base geometry and, where required, the optical light-guiding path.
This page covers rods with machined surface grooves. For a plain, ungrooved optical rod, see Quartz Light Guide Rods. A groove is an open surface feature and is different from the enclosed internal bores used in multi-bore quartz capillaries.
Groove Geometry
| Parameter | Specification |
|---|---|
| Groove Pattern | Straight, angular, V-shaped, spiral or stepped |
| Groove Width | Specified to drawing |
| Groove Depth | Specified to drawing |
| Groove Count | Single or multiple grooves on one rod; different widths and depths can be combined on the same component |
| Groove Surface Finish | Polished (Ra <0.05 µm), ground or fire-polished |
Rod Size
| Parameter | Specification |
|---|---|
| Base Rod Diameter | 1–100 mm |
| Length | Follows the base Quartz Light Guide Rod specification and finished drawing requirement |
| Base Geometry | Round fused quartz rod before groove machining |
| Groove Relationship | The groove is added to the base rod geometry; it does not use a separate rod-size system |
Cutting & Finishing
Cutting — Rods can be cut to finished length by diamond saw, wire cutting or abrasive waterjet, selected according to section size and precision requirement.
End Grinding & Polishing — Where the rod also carries light through its end faces, additional grinding or optical polishing can be used to achieve high-quality coupling surfaces.
Surface Quality — 60/40 scratch-dig is the standard optical option; polished, ground or custom-textured surfaces are available according to the functional requirement.
Material Grade Options
| Grade Option | Use |
|---|---|
| Standard Fused Quartz | General optical and mechanical alignment components |
| Low-OH | Selected where OH content and IR transmission are part of the optical requirement |
| UV Grade | For applications requiring UV transmission through the rod body |
| IR Grade | For optical systems where infrared transmission is the primary material-selection driver |
For OH-content grade selection where UV or IR transmission through the rod matters, see Low-OH Fused Quartz.
End Finish
End condition follows Quartz Light Guide Rods when the grooved rod also functions as an optical light guide. Ends can be optically polished, chamfered or angled independently. If the groove is used only for mechanical positioning, the rod ends can instead be supplied cut or ground to the required assembly condition.
Thermal Stability
| Condition | Temperature |
|---|---|
| Continuous Use | Up to 1100°C |
| Short-Term Exposure | Up to 1450°C |
These temperature limits follow standard fused quartz rod stock. Actual service temperature should also consider groove geometry, mechanical loading and assembly conditions.
What to Specify
| Parameter | Quotation Input |
|---|---|
| Base Rod | Diameter, finished length and tolerance |
| Groove Pattern | Straight / angular / V-shaped / spiral / stepped |
| Groove Width | Width for each groove |
| Groove Depth | Depth for each groove |
| Groove Count | Number of grooves and angular position around the rod |
| Groove Finish | Polished / ground / fire-polished |
| End Finish | Cut / ground / polished / angled / chamfered for each end |
| Material Grade | Standard / Low-OH / UV / IR grade |
| Quantity | Prototype or production quantity |
FAQ
Can grooves be added to an existing light guide rod order, or is it a separate specification?
Specify the groove together with the base rod diameter, length and end finish on the same drawing. It is manufactured as one finished component rather than as a separate add-on part.
What’s the difference between a grooved light guide rod and a multi-bore capillary?
A groove is an open channel machined into the rod’s outer surface for external fiber or component seating. A multi-bore capillary contains fully enclosed internal bores running through the body.