A multiple path light source has a first and second laser source that generate low power continuous wave laser beam at wavelength .lamda.1 and .lamda.2 respectively. A pump laser source generates a high power pulsed narrow linewidth laser beam at wavelength .lamda.0. A first pair of DFGs convert the low power continuous laser beams at .lamda.1 and .lamda.2 to high peak power pulsed laser beams at wavelengths .lamda.1 and .lamda.2, and generate pulsed laser beams at wavelength .lamda.1.sub.DFG=.lamda.1*.lamda.0/(.lamda.1-.lamda.0) and .lamda.2.sub.DFG=.lamda.2*.lamda.0/(.lamda.2-.lamda.0). A second pair of DFGs receives the high peak power pulsed laser beams at .lamda.1 and .lamda.2 and the pulsed laser beams at .lamda.1.sub.DFG and .lamda.2.sub.DFG and generates laser beams at wavelength .lamda.3=.lamda.1*.lamda.2/(.lamda.2-.lamda.1) and .lamda.3.sub.DFG=.lamda.1.sub.DFG*.lamda.2.sub.DFG/(.lamda.2.sub.DFG-.lam- da.1.sub.DFG). A beam splitter combines the high power pulsed laser beam at wavelength .lamda.3 with the high power pulsed laser beam at wavelength .lamda.3.sub.DFG to form a single laser light.

 
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< Laser scanning unit with meniscus scan lens having asymmetric, negative curvature in the sub-scanning direction and absolute curvature values in the main-scanning direction that are maximal at the center and differing minimal values at each side

> Optical disc reading and reproducing apparatus
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