APPARATUS AND METHOD FOR DETECTING THE POWER LEVEL IN SINGLE AND MULTI-STRIPE INTEGRATED LASERS The purpose of the present invention is to provide an apparatus for detection of a laser output on a semiconductor wafer, especially where the laser and detector are formed by similar or simultaneous processes on the same substrate. A laser cavity and a detection cavity are formed on a semiconductor wafer. The two are formed in parallel such that each has a generally axial orientation. Light emitted laterally from the laser cavity is detected by the detection cavity. The amount of light detected can then be transformed into data, which in turn can be used to control the output of the laser. Advantages of the present invention include the ability to simultaneously form the laser and detector portions, the detector portion so formed does not interfere with the beam being provided by the laser, and the ability to integrate multiple laser-sensor pairs in a semiconductor device.