Diode Laser Diffraction with Imported Slides

Item Code: SK173

Working and Principle :

Diffraction phenomenon of light can be observed when a laser beam passes through a diffraction slit. The intensity pattern can be determined using a pin photo detector with fine movement across the diffraction pattern.

... In the present setup, the light intensity in the terms of current or voltage is noted at closed intervals by finely traversing the detector movement and observing the light intensity on a digital multimeter. The intensity versus distance curve is plotted on a graph for calculations. The device consists of one meter long optical bench with two transverse saddle for laser and slit mount and one transverse saddle with micrometer for detector. A number of diffraction slits and gratings are provided with this setup.




  • Pin hole with silicon photo detector.
  • Class I diode laser with output power 0.4 – 0.8 mV.
  • All individually slides are protected by two glass plates in frame.
  • Saddle can hold rod from 8 to 15mm.
  • Heavy, rigid and stable Triangular Optical bench (made of Al extrusion).
  • Height and level adjustment screws (made of SS)

  • Diffraction of light by single, double and multiple slit.
  • Diffraction of light by fine, cross wire & wire mesh.
  • Diffraction of light by transmission grating and by coarse grating.
  • Diffraction of light by circular aperture. (Pinhole).
  • Diffraction of light by grid and by grey filter.
  • Diffraction of light by tapered single slit and by circular opaque spots.
  • Optical bench : Al exclusion, L = 1 m, Triangular shape with end stop, 4 point levelling (SS screw)
  • Transversal slider : 25 – 0 – 25mm, LC 0.01mm
  • Screen : Acrylic (translucent) 300 x 300 x 3mm
  • Photo detector : Silicon photocell, 4mm safety socket, Aperture 1mm, rod 10mm dia.
  • Fixed slider : Al Extrusion, Base width 50mm, H 115mm
  • Connecting lead : Type Banana plug, Length 100cm
  • Diode laser : Wavelength 635nm, Operating voltage 5V DC, Optical power 0.4 – 0.8mW, Class I
  • Frame Size : 50mm x 50mm

    • Diffraction Slides

  • Slit : Width 0.06mm & Separation 0.20mm (Single, Double, Three, Four, Five, & Six) Single & Double slit Tapered
  • Coarse Grating : 4 & 8 lines/mm, line/space ratio 3:1 & 6:1
  • Diffraction grating : 80 lines / mm, 300 lines / mm
  • Circular apertures : 1.0, 0.60, 1.40, 0.30 mm nominal dia.
  • Hologram : 50 x 50mm Transmission type
  • Polaroids : 50 x 50mm linearly polarized
  • 1 Optical bench triangular
  • 4 Fixed slider
  • 1 Transversal slider
  • 1 Diode laser with power adaptor
  • 1 Slit holder
  • 1 Pin hole photo detector
  • 1 Digital multimeter
  • 1 Diffraction slides (Imported)
  • 1 Single wire
  • 1 Cross wire
  • 1 Connecting lead
  • 1 Diffraction grating (15000 lines)
  • 1 Object screen