A light grid having a transmission unit having a plurality of light transmitters for transmitting light beams, a reception unit having a plurality of light receivers for receiving the light beams, wherein the transmission unit and the reception unit are spaced apart from one another and are disposed opposite one another; wherein a monitored field is formed by oppositely disposed light transmitters and light receivers for detecting objects; wherein the light transmitters can be activated one after the other in cycles and the light receivers can be evaluated in these cycles, chrarcterized in that a programmable evaluation unit that is provided in the reception unit, wherein the evaluation unit is configured to evaluate received signals of the light receivers of a cycle with reference to predefined beam evaluation criteria and to form an intermediate result therefrom, wherein the intermediate result can be stored in a memory; wherein the non-relevant information from received signals are discarded after an evaluation using the beam evaluation criteria of the evaluation unit and information from receiving signals which do not allow an evaluation by beam evaluation criteria, as they do not correspond to any predetermined beam evaluation criteria, are discarded such that this information are not being stored, whereby no storage space is required and the evaluation unit is further configured to evaluate at least one intermediate result of a respective cycle with reference to at least one respective predefined sequential criterion; and wherein the evaluation unit is also configured to output at least one output signal at at least one output on the basis of the evaluated intermediate result, wherein the beam evaluation criteria. are predefined and at least one of the following beam evaluation criteria can be set: - a predetermined, fixed light beam is interrupted; - a predetermined, fixed light beam is not interrupted, but free; - a central light beam is interrupted; - a central light beam is not interrupted, but free; - a first light beam is interrupted; - a first light beam is not interrupted, but free; - a continuous and associated number of light beams is interrupted; - a continuous and associated number of light beams is not interrupted, but free; - a last light beam is interrupted; - a last light beam is not interrupted, but free; - a predetermined, fixed number of light beams is interrupted; - a predetermined, fixed number of light beams is not interrupted, but free, and the sequential criteria are predefined, and at least one of the following sequential criteria can be set: - branching when a set beam evaluation criterion is satisfied; - recording time until a set beam evaluation criterion is satisfied; - recording a count; - deleting an intermediate result marker; - storing an intermediate result marker; - logical OR link of intermediate results; - logical AND link of intermediate results; - inverting intermediate results; - changing a function, setting or configuration of the light grid; - reading in at least one input value of at least one input. - a predetermined, fixed light beam is interrupted; - a predetermined, fixed light beam is not interrupted, but free; - a central light beam is interrupted; - a central light beam is not interrupted, but free; - a first light beam is interrupted; - a first light beam is not interrupted, but free; - a continuous and associated number of light beams is interrupted; - a continuous and associated number of light beams is not interrupted, but free; - a last light beam is interrupted; - a last light beam is not interrupted, but free; - a predetermined, fixed number of light beams is interrupted; - a predetermined, fixed number of light beams is not interrupted, but free, and the sequential criteria are predefined, and at least one of the following sequential criteria can be set: - branching when a set beam evaluation criterion is satisfied; - recording time until a set beam evaluation criterion is satisfied; - recording a count; - deleting an intermediate result marker; - storing an intermediate result marker; - logical OR link of intermediate results; - logical AND link of intermediate results; - inverting intermediate results; - changing a function, setting or configuration of the light grid; - reading in at least one input value of at least one input.