Optical Bench

DO NOT LOOK DIRECTLY INTO BEAM

Normal Use

• Turn on power strip
• Put in standard and record image
• Put in negative of interest and record image
• If beam is diffuse realign camera
• If laser has been moved realign the optical bench

Aligning Optical Bench

Define optical Axis

1. Remove lenses
2. Remove objective aperture
3. Leave polarizing lens in
4. If two beams are visible the polarizing lens is not completely perpendicular to the beam
5. Center beam using a paper covered lens holder with a pin hole in center
6. Center laser using x-y controls
7. Move paper lens across axis to determine if beam is parallel
8. Once beam is parallel add objective lens

Alignment of Objective Lens

1. First unscrew the top lens
2. Roughly center assembly by using the coarse x-y translations until beam is just visible
3. Use a piece of paper to view beam and continue to adjust x-y until maximum brightness is achieved
4. Reinsert the top lens and screw down
5. Use the fine x-y translations (on assembly) to achieve maximum bright ness
6. Make sure beam is still on axis

Focusing Camera

• Focus camera by adjusting height
• Tighten camera very well

Setting Height of Field Limiting Aperture and Parallel Lens

1. Add parallel lens below field limiting aperture on same base plate
2. Use piece of paper to make sure aperture does not appear to change size on axis between aperture and camera - If aperture appears to shrink moving towards camera lower aperture and vise versa