Breckland Scientific 2023 Catalogue

Optics

Properties of Light

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1 LASCELLS PLANCK’S CONSTANT A selection of LEDs cover the range from deep blue to infra-red. By monitoring the voltage at which each LED just begins to emit light, a graph of energy input as a function of light emitted frequency can be plotted and an approximate value of Planck’s constant deduced. The system is an excellent illustration of modern electronics and gives a good investigation into a difficult topic in Post-16 physics. The LEDs are mounted in a self-contained box with voltage control and monitoring points for current and voltage. A protection resistor is included to prevent damage to the LEDs. Complete with viewing tube but requires a 5V d.c. lab. power supply. Cat No. Description Price Per ATQ-305-100 Planck’s Constant 84.42 ea. 2 DIFFRACTION GLASSES Simple diffraction glasses for seeing light sepa- rated into its constituent parts. Cat No. Description Price Per OPL-050-100 Diffraction Glasses 8.40 10pk 3 DIFFRACTION GRATINGS SLIDE A three window diffraction grating slide in a single holder, for demonstrating diffraction of light through gratings with different line spacings. The slide includes 3 rulings, one each of of 100 lines/ mm, 300 lines/mm, and 600 lines/mm. Each aperture is 16 x 9mm. Overall slide size: 89 x 32mm. Cat No. Description Price Per OPL-150-100 Diffraction Gratings Slide 27.60 ea. 4 DIFFRACTION GRATINGS A range of 35mm format diffraction grat- ings slides, mounted in 50mm carriers. The gratings are cut onto glass and mounted in a 50 x 50mm plastic slide frame, with a protective glass coverslip. Aperture size: 36 X 24mm. Cat No. Description Size Price Per OPL-100-100 Diffraction Gratings 80 lines/mm 16.63 ea. OPL-100-150 Diffraction Gratings 100 lines/mm 16.63 ea. OPL-100-200 Diffraction Gratings 300 lines/mm 16.63 ea. OPL-100-250 Diffraction Gratings 600 lines/mm 23.17 ea. OPL-100-300 Diffraction Gratings 1200 lines/mm 23.17 ea. 5 LASCELLS POLAROID ANALYSER - NEW! The Polaroid analyser provides a convenient method for analysing polarisation of light, and stress in suitable materials. Polaroid sheet acts like a “grid” and allows only light waves oscillating in one plane to pass through. If another polaroid sheet is placed in front of the first, and aligned in the same direction, the polarised light from the first will pass through the second since the waves are in the correct plane. If the second polaroid is rotated through 90 degrees none of the waves will be able to pass and little light is transmitted. This system is known as “crossed polarisers” and is used in this apparatus. Some materials have the property of rotating the plane of polarisation of light and when placed between the crossed polarisers allow some of the light to pass. Furthermore, stresses in the material change the amount of rotation and this change is also dependent upon the wavelength of the light. Col- oured patterns are therefore produced which give information about the stresses in the material. Cat No. Description Price Per OPL-575-100 Lascells Polaroid Analyser 27.07 ea. 6 LASCELLS STRESS STRUCTURE SET - NEW! A set of four additional shapes for use with the polaroid analyser, and a sheet of material 200 × 200 × 2mm from which other shapes may be cut. Cat No. Description Price Per OPL-585-100 Stress Structure Set 29.50 set

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Lascells Planck’s Constant

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Diffraction Glasses

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Diffraction Gratings Slide

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Diffraction Gratings

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Lascells Polaroid Analyser

Lascells Stress Structure Set

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