We introduce a simple, compact, and automatically distortion-free single-grism pulse compressor that can compensate
for large amounts of material dispersion in ultrashort pulses, which increases the pulse duration and decreases the peak
intensity. Diffraction-grating pulse compressors can compensate for high dispersion, but they do not compensate for
higher-order dispersion (important when GDD is large). Worse, all previous general-purpose grating designs have
involved multiple gratings and so are also difficult to align and prone to distortions: small misalignments cause
unwanted spatio-temporal pulse distortions. A compressor based on grisms solves the higher-order-dispersion problem
because grisms allow the ratio of third-order to second-order dispersion to be tuned to match that of the material that
introduced the GDD. A grism can also compensate for large amounts of dispersion. Unfortunately, previous grism
compressors used multiple grisms and so are difficult to align and prone to spatio-temporal distortions. To overcome this
problem, we introduce a single-grism compressor. It comprises only three elements: a reflection grism, a corner cube,
and a roof mirror. SEA TADPOLE measured the compressor GDD and third-order dispersion, verifying its operation.
This convenient device should be a valuable general tool.