The 1-Photon SLM Microscopy Kit is a scan-less SLM-based epi-fluorescence upright microscope that enables three dimensional calcium imaging and/or photoactivation of neurons in brain slices. The microscope can be used to excite and monitor activity of neuronal ensembles, enabling studies of neuronal circuit activity both in vitro and in vivo. Add-on to existing microscope or use as stand-alone microscope.