Inventor · Morristown, NJ, US

Ralph A. Logan

21Patents
11h-index
14Co-inventors
68Inventor score

Filing activity: Jun 20, 1974 → Aug 7, 1990

Most-cited inventions

PatentTitleAreaCited byStatus
US4093345A Semiconductor rib waveguide optical modulator with heterojunction control electrode cladding Physics 50 Expired
US3978426A Heterostructure devices including tapered optical couplers Emerging Cross-Sectional Technologies 38 Expired
US4136928A Optical integrated circuit including junction laser with oblique mirror Electricity 34 Expired
US3993963A Heterostructure devices, a light guiding layer having contiguous zones of different thickness and bandgap and method of making same Electricity 34 Expired
US5040186A InP-based quantum-well laser Electricity 20 Expired
US4159452A Dual beam double cavity heterostructure laser with branching output waveguides Electricity 19 Expired
US4575919A Method of making heteroepitaxial ridge overgrown laser Emerging Cross-Sectional Technologies 19 Expired
US4390889A Photodiode having an InGaAs layer with an adjacent InGaAsP p-n junction Electricity 17 Expired
US4269635A Strip buried heterostructure laser Emerging Cross-Sectional Technologies 13 Expired
US4190813A Strip buried heterostructure laser Electricity 13 Expired
US4226667A Oxide masking of gallium arsenide Emerging Cross-Sectional Technologies 12 Expired
US4169997A Lateral current confinement in junction lasers Electricity 11 Expired
US3935472A Thin film liquid waveguide optical converter Physics 10 Expired
US4464211A Method for selective area growth by liquid phase epitaxy Electricity 10 Expired
US4701995A Method of making a nonplanar buried-heterostructure distributed-feedback laser Electricity 9 Expired
US4953170A Method for forming a heteroepitaxial structure, and a device manufactured thereby Electricity 8 Expired
US4028146A LPE Technique for fabricating tapered optical couplers Emerging Cross-Sectional Technologies 8 Expired
US4627065A Double active layer semiconductor laser Electricity 6 Expired
US4194933A Method for fabricating junction lasers having lateral current confinement Electricity 6 Expired
US4481631A Loss stabilized buried heterostructure laser Electricity 4 Expired
US4536940A Method of making a loss stabilized buried heterostructure laser Emerging Cross-Sectional Technologies 4 Expired

Source: USPTO / EPO open patent data. Inventor disambiguation is heuristic; counts are objective bibliographic measures.