This paper describes an innovative, high throughput manufacturing test system for testing high power laser-diode stacks. These stacks are based on a single high power bar building block, which can be stacked either vertically or horizontally to deliver extremely high output power (>3kW) from a compact package which can range from a single bar to over 25 bars in one package. Testing these various form-factors presents many challenges in high-volume manufacturing e.g.
repeated changes of tooling and set-up to accommodate mixture of configurations. The automated test system described in this paper can accommodate any configuration of multi-bar stacks to test critical optical characteristics (LIV, Optical Spectrum Characteristics, Optical Power, Optical Divergence, water flow rate, water pressure etc.). Key to the automated station is a custom designed integrating sphere and universal stack holder with automated water flow
configuration. The automated test system significantly improves the throughput by decreasing the test time by 50% (compared to manual testing). Individual bars comprising stack have different spectrum and the custom designed integrating sphere enables accurate spectrum analysis (centroid wavelength, FWHM) of the combined spectrum, as well as accurate power measurement.