CM March14

Completed this week

We redesigned the confocal optical setup:

• The beam expander was integrated into the relay lenses. Now the setup has fewer parts to adjust.
• We will use an achromatic lens pair for the relay lenses.
• We have switched to 1 inch optics* instead of 2 inch optics
• The dichroic for the bright field image was moved in front of the relay lenses, after the objective (in the bright field beam path). The bright field image is not shrunk by the beam expander and we can be more confident in the appropriateness of 1 inch optics.
• The PMT is horizontal instead of vertical for greater stability
• The pinhole screws onto the z-direction adjuster so pinhole sizes can be swapped without difficulty
• Spacial placement of beam path is such that a second laser and a photodiode (for laser intensity measurements) can be added easily in the future and such that the amount of beam expansion is easily changed.

.*In order to use 1 inch optics, the distance between the galvo mirrors and the first relay lens had to be less than (1 inch)/tan(theta) where theta is the maximum angle of the galvos needed to cover the whole field of view of the objective, 7.1 degrees.

We began building the new setup

• We got a new bread board (so we don't have to dismantle the old setup yet)
• We built the whole beam path

We wrote a first draft of our budget

To do next week

• Divide the budget into "necessary" and "nice" components and order the parts we need immediately
• Add mirrors, dichroics, LED, laser (etc) into the beam path
• Get in contact with Nikon and/or do math to determine maximum beam expansion for the 100x objective lens we are using. Modify optical design accordingly.