Light and Optics

Newton’s rings with interference filters

Principle In a Newton’s rings apparatus, monochromatic light interferes in the thin film of air between the slightly convex lens and a plane glass plate. The wavelengths are determined from the radii of the interference rings. Benefits the color of soap bubbles is based on it: interference in thin films use interference optics to determine […]

Faraday’s laws

Principle   Faraday’s first law states that the mass of a material separated by electrolysis is proportional to the quantity of electricity which flowed through the solution. The second law states that the electrochemical equivalents are proportional to their equivalent masses (molar mass divided by valency). The experimental setup depicted here can be used to […]


Principle The rotation of the plane of polarisation through a sugar solution measured with a half-shade  polarimeter and the reaction rate constant for the inversion of cane sugar determined. Benefits even transparent fluids can change the properties of light passing them find out how fast one type of sugar changes into another one use optical […]

Michelson interferometer

Principle In the Michelson arrangement interference will occur by the use of 2 mirrors. The wavelength is determined by displacing one mirror using the micrometerscrew. Benefits discover the essence of the Physics Nobel Prize of 1907 lead to experimental findings that only special relativity theory could explain pre setup of the critical components makes for […]

Index of refraction, dipersion, and resolving power of a prism spectroscope

Principle The spectrometer-goniometer is used to determine the angle of deflection that light undergoes when passing a prism. The refractive index of a prism at the specific wavelength of a known spectral line can be determined by observation of the angle of least deflection of light of that spectral line effected by that prism, given […]

Faraday effect

Principle The angle of rotation of the polarisation- plane of plane polarised light through a flint glass rod is found to be a linear function of the product of the mean flux-densitiy and the length of the optical medium. The factor of proportionally, called Verdet’s constant, is investigated as a function of the wavelength and […]

Malus’ law

Principle Linear polarised light passes through a polarisation filter. Transmitted light intensity is determined as a function of the angular position of the polarisation filter. Benefits the principle that Polaroid glasses work on introductory yet quantitative experiment to polarization straightforward simple setup Tasks The plane of polarisation of a linear polarised laser beam is to […]

Polarisation through quarter-wave plates

Principle Monochromatic light falls on a mica plate perpendicular to its optic axis. At the appropriate plate thickness (lambda/4, or quarter-wave plate) there is a 90° phase shift between the ordinary and the extraordinary ray when the light emerges from the crystal. The polarisation of the emergent light is investigated at different angles between the […]

X-ray investigation of crystal structures / Laue method

Principle Laue diagrams are produced when monocrystals are irradiated with polychromatic X-rays. This method is primarily used for the determination of crystal symmetries and the orientation of crystals. When a LiF monocrystal is irradiated with polychromatic X-rays, a characteristic diffraction pattern results. This pattern is photographed and then evaluated. Tasks The Laue diffraction of an […]

Examination of the structure of NaCl monocrystals with different orientations

Principle The spectra of the X-rays that are reflected with various different orientations by NaCl monocrystals are analysed. The associated interplanar spacings are determined based on the Bragg angles of the characteristic lines. Tasks Determine the intensity of the X-rays that are reflected by the NaCl monocrystals with the orientations [100], [110] and [111] as […]

Magnetostriction with the Michelson interferometer

PrincipleWith the aid of two mirrors in a Michelson arrangement, light is brought to interference. Due to the magnetostrictive effect, one of the mirrors is shifted by variation in the magnetic field applied to a sample and the change in the interference pattern is observed. Benefits See that magnetic fields can change the geometry of […]

Fabry-Perot interferometer – optical resonator modes

Principle Two mirrors are assembled to form a Fabry-Perot interferometer. Using them, the multibeam interference ofa laser’s light beam is investigated.On moving one of the mirrors, thechange in the intensity distributionof the interfeence pattern is studied. This is a qualitative experiment,to study the shape of different lasermodes and compare it with some photosgiven in this […]

Quantum eraser with the Mach-Zehnder interferometer

Principle A Mach-Zehnder-interferometer is illuminated with a laser beam. Circular interference fringes appear on the screens behind the interferometer. If polarisation filters with opposite polarisation planes are placed in the two interferometer paths the interference patterns disappear. Placing another polariser before one of the screens causes the pattern to reappear. Electromagnetic radiation can be described […]

Diffraction intensity at a slit and at a wire – Babinet’s theorem

Principle An aperture consisting of a single slit and a complementary strip (wire) is illuminated with a laser beam. The corresponding diffraction patterns are measured according to position and intensity with a photocell which can be shifted. Benefits surprisingly a slit and a wire show basically the same diffraction pattern measurements prove a theorem that […]

Diffraction intensity due to multiple slits and grids

Principle Multiple slits which all have the same width and the same distance among each other, as well as transmission grids with different grid constants, are submitted to laser light. The corresponding diffraction patterns are measured according to their position and intensity, by means of a photo diode which can be shifted. Benefits understand what […]

Diffraction of light at a slit and an edge

Principle Monochromatic light is incident on a slit or an edge. The intensity distribution of the diffraction pattern is determined. Benefits learn that the transition region from light to shadow is not a sharp line, but a diffraction pattern you can make use of diffraction patterns to determine properties of the objects causing them simple […]

Michelson interferometer – High Resolution

Principle With the aid of two mirrors in a Michelson arrangement, light is brought to interference. While moving one of the mirrors, the alterationin the interference pattern is observed and the wave length of the laser light determined. Benefits Learn about the measurement principle with which gravitational waves can be observed Assemble your own interferometer using invidual optical components […]

Refraction index of air and CO2 with the Michelson interferometer

Principle A measurement cuvette set in the beam path of a Michelson interferometer can be evacuated or filled with CO2. The refraction indexes of air or CO2 are determined through the assessed modification of the interference pattern. Benefits see that even two transparent gases can have different optical properties a Michelson interferometer is used to measure subtle differences […]

Coherence and width of spectral lines with the Michelson interferometer

Principle The wavelengths and the corresponding lengths of coherence of the green spectral lines of an extreme high pressure Hg vapour lamp are determined by means of a Michelson interferometer. Different double slit combinations are illuminated to verify the coherence conditions of non punctual light sources. An illuminated auxiliary adjustable slit acts as a non […]

Structure of a Fresnel zone plate

Principle A zone plate is illuminated with parallel laser light. The focal points of several orders of the zone plate are projected on a ground glass screen. Benefits find out that optical lenses can be completely different from what you are used to interference is used to produce effects commonly achieved with diffraction the use […]

Laws of lenses and optical instruments

PrincipleThe focal lengths of unknown lenses are determined by measuring the distances of image and object and by Bessel’s method. Simple optical instruments are then constructed with these lenses. Tasks To determine the focal length of two unknown convex lenses by measuring the distances of image and object. To determine the focal length of a […]

Fibre optics

Principle The beam of a laser diode is treated in a way that it can be coupled into a monomode fibre. The problems related to coupling the beam into the fibre are evaluated and verified. In consequence a low frequency signal is transmitted through the fibre. The numerical aperture of the fibre is recorded. The […]

Fresnel’s law – theory of reflection

Principle Plane-polarized light is reflected at a glass surface. Both the rotation of the plane of polarization and the intensity of the reflected light are to be determined and compared with Fresnel’s formulare for reflection. Benefits see that reflection at a glass surface changes some properties of light find out that at special angles, light […]

Interference of light

Principle By dividing up the wave-front of a beam of light at the Fresnel mirror and the Fresnel biprism, interference is produced. The wavelength is determined from the interference patterns. Benefits observe that light plus light can result in darkness understand how to make use of the interference effect a laser as lightsource allows clear […]

Dispersion and resolving power of a grating spectroscope

Principle The diffracted light from a periodic line grating is observed with a goniometer. The diffraction angles of spectral lines in different orders of diffraction are measured for the spectral lines from a Hg spectral lamp. By using gratings with different grating constants the angular spectral dispersion in dependence on grating constant is determined. The […]

Lambert’s law of radiation on optical base plate

Principle Visible light impinges on a diffusely reflecting surface. The luminance of this surface is determined as a function of the angle of observation. Benefits study the light intensity that a sheet of paper is diffusely reflecting learn about the different physical units associated with light very versatile optical base plate Tasks The luminous flux […]

Photometric law of distance with Cobra4 – inverse square law

Principle The luminous intensity emitted by a punctual source is determined as a function of distance. Benefits find out how exactly it becomes darker with increasing distance from a lightsource get results fast and reproducible with a data-logging system analize results easily and compare them to theory using a computer Tasks The luminous intensity emitted […]

Measuring the velocity of light

Principle The intensity of the light is modulated and the phase relationship of the transmitter and receiver signal compared. The velocity of light is calculated from the relationship between the changes in the phase and the light path. Benefits determine yourself what the “speed of light” actually is find out how the velocity of light […]