Spherically mounted retroreflectors (SMRs or optical targets) are an important part of the FARO® Laser Tracker system. Handle them with great care to ensure their accuracy and longevity.
- Never touch the optical surfaces of the target.
- Never drop the target.
- Keep the target free of dust and moisture by storing it in the case.
- Clean the target only when necessary.
CAUTION: Unnecessary cleaning degrades the reflective surface of the SMR and causes damage to the coatings on silver surfaces that can destroy the SMR. Only clean SMRs when required for proper measurement and accuracy performance, not based on cosmetic conditions.
Check if the SMR Needs Cleaning
If the Laser Tracker Measuring Head does not lock onto the target, use the Operational Checks command to check if your SMR needs cleaning. If the Return Power value is GOOD, your SMR does not need cleaning.
Click here to get proper cleaning supplies and Optima grade acetone.
In some cases, the optical surfaces of the SMR are dusty. You can clean SMRs with canned compressed air.
CAUTION: Do not use compressed air from a workshop compressor hose. Air from a compressor hose is seldom clean and may coat the SMR with oil or other contaminant.
Follow these guidelines when spraying canned compressed air onto SMR optical surfaces.
- Spray air away from the SMR for a few seconds before spraying it onto the optical surfaces. This removes any propellant in the can from the air nozzle and prevents the propellant from being sprayed onto the SMR’s optical surfaces.
- Always hold the can upright.
- Never shake the can when spraying compressed air.
If the SMR is still not functional after removing dust, follow these steps.
CAUTION: Never use a dry cotton swab or tissue to clean SMR optical surfaces. These may scratch the optical surfaces.
Cleaning with improper materials and chemicals can destroy the reflective surface. Click here for links to articles about proper materials and chemicals.
- Breathe on the optical surfaces. The moisture in your breath forms a layer of condensation on the glass surface.
- While condensation is still on the glass surface, gently slide a clean cotton swab in one direction while rotating it in the opposite direction. Use very little pressure, do not push the cotton swab onto the surface.
- Use one cotton swab for each pass, and then discard it. You may need several swabs to clean the optical surfaces thoroughly. Using a cotton swab more than one time can cause debris to scratch the coatings and on silver SMRs, a scratch can lead to oxidation under the coatings and destroy the SMR.
- If this does not successfully remove the residue, clean the optical surfaces with Optima grade acetone for oil based residue or denatured alcohol for water based residue.
- Moisten a clean cotton swab with solvent.
- Gently slide the cotton swab in one direction while rotating it in the opposite direction. Use very little pressure, do not push the cotton swab onto the surface. Use one cotton swab for each pass and then discard it. You may need several swabs to clean the optical surfaces thoroughly.
- Remove any remaining cotton dust with canned compressed air.
- Repair and Refurbishment Options for the Break Resistant SMR
- SMR Window Replacement Availability
- Laser Tracker Target Information, Troubleshooting, and Use and Care
- Factory Certification Tests Performed on Laser Tracker SMR
- Certificate of Calibration Information for the SMR
- Technical and Environmental Specifications for Laser Tracker Targets (SMRs)
clean, care, optical targets, cleaning