PARTICLE SIZE MEASUREMENT
Item Code : SK172
Principle and Working:
An expanded He-Ne laser beam is shone through a plate dusted with lycopodium powder, forming circular rings on the screen. These rings are nearly spherical and have a uniform average diameter. The quality of the rings depends on the even distribution of the lycopodium powder. The wavelength of the given laser source is given by:
Where:
N = Number of lines per meter of the grating.The grain size (diameter) 2d of the grain is given by:
Where
n – Order of diffraction.
ʎ – Wavelength of the laser used (in meters).
D – Distance between the glass plate and the screen (in meters).
Xn– Distance between the central bright spot and the nth fringe (in metre).
- Pin hole with silicon photo detector.
- Diode laser with output power 3-5 mW.
- All individually slides are protected by two glass plates in frame.
- Saddle can hold rod from 8 to 15mm.
- Heavy, rigid and stable optical bench.
- Height and level adjustment screws.
- 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 : Length – 1 mtr. with Scale, 4 point levelling. Material Aluminium or MS.
- Photo detector : Silicon photocell, 4mm safety socket, Aperture 1mm, rod 10mm dia.
- Diode laser : Wavelength 635nm, Operating voltage 5V DC, Optical power 3-5mW.
- Diffraction slides : SL744.
- Frame Size: 50mm x 50mm, 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 Transmission type.
- Polaroids : linearly polarized.
- Set of 13 Objects : Single slit, double slit, multiple slit 3, multiple slit 4, multiple slit 5, single tapered slit, fine grating, 4 holes, circular opaque spots. gray filter, mesh, coarse grating & grid pattern.
| S.No. | Item Name | SK078 | SK173 |
|---|---|---|---|
| 1 | Transverse Slider | 1 | 1 |
| 2 | Fixed Slider | 3 | 3 |
| 3 | Optical Bench with Levelling | 1 | 1 |
| 4 | Slit Holder | 1 | 1 |
| 5 | Single Wire Slit | 1 | 1 |
| 6 | Cross Wire Slit | 1 | 1 |
| 7 | Diode Laser (Red) | 1 | 1 |
| 8 | Adaptor 5V/1A | 1 | 1 |
| 9 | Digital Multimeter 4½ Digits | 1 | 1 |
| 10 | Cylindrical Base | 1 | 1 |
| 11 | Diffraction Slides (imported) | 1 | — |
| 12 | Diffraction on grating 600 line per mm | 1 | 1 |
| 13 | Pin Hole Photo Detector | 1 | 1 |
| 14 | Flexible Plug Lead 100mm (Black) | 1 | 1 |
| 15 | Flexible Plug Lead 100mm (Red) | 1 | 1 |
| 16 | Translucent Screen 300×300 mm | 1 | 1 |
| 17 | Measuring Tape | 1 | 1 |
| 18 | Set of 13 Diffraction Slides | — | 1 |
Note : The standard supply is the Hexagonal Optical Bench (MS). To request the Triangle Optical Bench (Aluminium Extrusion),please specify in your request.