Optical pump modules using VCSEL arrays are provided to pump optical gain media for achieving high power laser output in CW, QCW and pulse operation modes for operation. Low divergence and symmetric far-field emission from VCSELs are particularly suitable for compact arrays. VCSEL arrays configured as laser pump modules are operable at high temperatures with practically no degradation over a long period of time. VCSEL pump modules are adaptable for side- or end-pumping configurations to pump high power lasers in CW, QCW and pulse mode. Power output from VCSEL pump modules is scalable. Incorporating microlens arrays with the VCSEL arrays improve brightness of the pump modules. High power and high temperature operation of VCSEL modules make it suitable for making compact high power solid state lasers that are operable in small spaces such as, ignition of internal combustion engines, stationary power generation engines and pulsed detonation engines.