The Projecting Microscope

1. The Projecting Microscope A sample presentation by Chuck Rogers, Dept. of Physics, CU-Boulder Projection Microscope

2. Learn how to use the optics lab room equipment. • Hit the high points of observing and understanding laser beam properties and diffraction. • Design a 400x projecting microscope • Build the microscope and verify its behavior. Major Goals Projection Microscope

3. The Optics Lab • What’s in the cabinet? • Setup the laser on the optical rail. • Fiddle with Ronchi and lenses. • Learn how to find lenses. Projection Microscope

4. Ronchi Grating (a spatial square wave) Diffraction pattern through the Ronchi. Shows only odd orders, consistent with a square wave. Measuring microscope view of the Ronchi grating. A ten period average shows a square wave period of 254 ± 3 microns/line. 15 fringes covered 68 ± 1 mm and the screen was 1840 ± 5 mm away so tan(q) = 0.0370 ± 0.0006. Diffraction theory predicts l=d Sinq/N which gives Measured laser wavelength: 627 nm +/- 13 nm Although only a 2% measurement (13/627), it is within 1% of the true wavelength (632.8 nm) Projection Microscope

5. Design of the 400x Projection Microscope 4x beam expander. Used Lx1 f.l.=25mm and lens Lx2, f.l.=100mm Two magnification stages of equal mag of 20x Built with equal focal length lenses f.l. = 50mm Projection Microscope

6. Sample images High resolution image of a single atomic state imaged with our microscope. Projection Microscope

7. Diffraction limits of resolution Modest choppiness on the image due to finite laser wavelength. We saw no effect from the iris because we put it in front of the beam expander rather than the first lens…. Projection Microscope

8. Learned how to use the optics lab room equipment. • Hit the high points of observing and understanding laser beam properties and diffraction. • Designed a 400x projecting microscope • Build the microscope and verified its behavior. Summary Projection Microscope