6C10.10 Single Slit Diffraction

Shine laser beam through slit to produce diffraction pattern. Slide has several slit widths.

Setup Requirements:Assembled as needed. Dark room needed. Only center and first order visible from back of large room. Use  bright laser with separate power supply.

Equations: width x sin(A)= n x wavelength

Safety Issues: Laser has ten times power of pointer. 

6C10.15 Adjustable Single Slit Diffraction

Shine laser beam through narrow slit to produce diffraction pattern. Width of slit is adjustable.

Setup Requirements: Minimal. Use bright laser with separate power supply. Need dark room. Only center and first order visible from back of large room

Equations: width x sin(A) = n x wavelength

Safety Issues: Laser has 10 times power of pointer.

6C20.10 Diffraction Around Objects

Shine laser beam on small object to produce diffraction pattern. A pin works well. Concave lens needed to widen laser beam. Center of shadow is bright not dark. Produces a diffraction pattern that is similar to single slit. Pattern is too small to see from seats in large lecture rooms. Use web camera to show to class.

Setup Requirements: Ask ahead of time. Some time needed to assemble and test.Try small sphere (Arago/Poisson spot), or pin. If using web camera, click on Applied Vision 4 icon to put image on monitor.

Equations: Babinet's principle.

Safety Issues: Laser

6C20.30 Diffraction Pattern Using Round Opening

Shine laser beam on hole in slide to produce diffraction pattern. Pattern limits ability to separate binary stars using telescope.

Setup Requirements: Dark room needed. Pattern not visible from back of large lecture rooms. Use extra bright laser.

Equations: Position of first minimum given by sin(A) = 1.22 x wavelength / diameter

Safety Issues: Bright laser has 10 times power of pointer.

6C20.31 Diffraction Pattern Using Round Opening In Laser

The new smaller laser from Metrologic produces a good example of diffraction pattern produced by a round opening just using the hole the laser beam comes through.

Setup Requirements: Dark room needed. Pattern not visible from back of large lecture room.

Equations: Position of first minimum given by sin(A) = 1.22 x wavelength / diameter

Safety Issues: Laser