  In recent times, spatial light modulators have become a common tool in optics
laboratories as well as industrial environment to shape the spatial structure
of a beam. Although these devices are often easy to use, they usually come at a
high cost such that they are far from being implemented in a lot of
undergraduate laboratories. However, over the last years, the progress in
developing more cost-effective projectors has led to affordable spatial light
modulators in the form of so-called Digital Micromirror Devices (DMD). This
reduction in price, as well as their simple usage, make such devices
increasingly suitable for undergraduate laboratories to demonstrate optical
effects and the shaping of light fields. Here, we show one of the most
cost-effective ways to make a DMD available, namely turning a projector
evaluation module into a computer-controlled spatial light modulator. We
explain the underlying functioning and how this low-cost spatial light
modulator can be used in undergraduate laboratories. We further characterize
the efficiency of the device for the most commonly used laser wavelengths and
demonstrate various exemplary optics experiments suitable for undergraduate
laboratories ranging from single and multi-slit diffraction, to optical Fourier
transformations. Lastly, we show that using amplitude holography, the device
can be used to generate transverse spatial modes, e.g. Laguerre-Gaussian beam,
which are one of the most commonly used spatially structured beams.
