A professional who performs any combination of following duties to assemble optical instruments, such as telescopes, level-transits, and gunsights. Responsibilities include:

• Reads work order, blueprints, and sketches to determine assembly procedure.
• Cleans elements, using tissue, cleaning solution, and compressed air device.
• Coats optical elements according to specifications.
• Cements multiple lens assemblies together.
• Picks up element, using vacuum-holding device, and positions element in mounting seat of instrument housing.
• Inserts and screws locking ring in housing to hold element in place.
• Applies cement to rings to prevent loosening.
• Assembles structural and mechanical parts of instrument according to blueprint specifications, using wrenches and screwdrivers.
• Computes standard trigonometric formulas to determine distance of test target from instrument.
• Positions target in darkroom tunnel and connects optical instrument to test devices, such as oscilloscope and collimator.
• Sights instrument on target and reads dials to determine optical centre of instrument lens and to verify specified focusing power.
• Measures elements and instrument parts to verify dimensional specifications, using precision measuring instruments.
• Records inspection and test data.
• May set up and operate lathe to modify instrument parts.
• May paint instrument parts, using brush or spray gun.
• May fill instrument housing with nitrogen gas to minimise corrosive effects on internal optical surfaces, using vacuum pump.