Do you know the cleaning methods for microscopes?
Blow off surface dust with clean dry air. If dust cannot be removed completely, take two pieces of lens tissue, wrap them around a cotton swab, or fold the lens tissue to a size slightly larger than the area to be cleaned.
When wiping the surface of optical components, first clean the frosted surface and frame with petroleum ether.
When wiping circular components, move the cotton ball in a spiral path from the center toward the edge. Rotate the cotton ball itself at the same time, and slide the cotton ball off the lens surface smoothly. Do not pause at the lens edge to avoid leaving marks. If a rotary holder is used for wiping, move the cotton ball in a straight line from the center toward the edge while rotating the cotton ball (the cotton ball shall rotate slightly less than one full turn).
When wiping prisms, place the cotton swab horizontally on the surface to be wiped and perform wiping in straight strokes.
Wipe in a relatively clean room, and use degreased long-staple cotton swabs. Do not load excessive cleaning solution on the swab. Wipe in cross directions along the scribed lines of the reticle, so as not to wipe off the filler inside the scribed grooves.
When wiping cemented optical components, do not use excessive mixed solution on the cotton ball, otherwise the solvent may seep into the cement layer and cause delamination.
For aluminized reflective components with protective films: if the protective film is relatively firm, wipe it with a cotton ball slightly moistened with mixed solution or fine degreased gauze.
Roll the cotton properly; the bamboo stick of the rolled swab shall not be exposed to avoid scratching the components. The size and shape of the cotton ball shall match the size and type of the component. Generally, cylindrical cotton balls are used for circular components and flat cotton balls for planar components. Use soft cotton balls for coated surfaces (especially reflectors); roll the cotton tightly for all other cases.
When dipping the cotton ball with mixed solution into the solvent, the immersed length shall not exceed one‑third of the cotton ball.
