Inventor · McDowell, VA, US

Raphael L. Levien

32Patents
12h-index
4Co-inventors
74Inventor score

Filing activity: Jun 22, 1982 → Jul 8, 2016

Most-cited inventions

PatentTitleAreaCited byStatus
US5218386A Eyeglasses with spectral color shift Electricity 92 Expired
US5544258A Automatic tone correction of images using non-linear histogram processing Physics 87 Expired
US4523271A Software protection method and apparatus Physics 51 Expired
US5055942A Photographic image reproduction device using digital halftoning to screen images allowing adjustable coarseness Electricity 32 Expired
US5388517A Method and apparatus for automatic alignment of objects and register mark for use therewith Physics 29 Expired
US6097855A Method and apparatus for image rotation Electricity 28 Expired
US5155588A Color correction and apparatus for photographic reproduction Electricity 26 Expired
US5442461A Screen generation for halftone screening of images with reduction of irrational correction artifacts Electricity 24 Expired
US5524162A Method and apparatus for adaptive sharpening of images Physics 24 Expired
US5276535A Method and apparatus for halftoning of images using grayscale error diffusion Electricity 22 Expired
US5917614A Method and apparatus for error diffusion screening of images with improved smoothness in highlight and shadow regions Electricity 20 Expired
US5337264A Time reversal gaussian approximation filter Electricity 17 Expired
US5402726A Register mark Physics 12 Expired
US5291310A Screen generation for halftone screening of images Electricity 12 Expired
US5315406A Screen generation for halftone screening of images using arbitrary distribution of transformed screen coordinates Electricity 12 Expired
US5331429A Digital generation of halftone images with error diffusion and frequency matched periodic screen rulings Electricity 11 Expired
US5307181A Screen generation for halftone screening of images using scan line segments of oversized screen scan lines Electricity 10 Expired
US5404137A High speed transition signalling communication system Physics 10 Expired
US5991513A Method and apparatus for suppressing moire patterns Electricity 6 Expired
US5365602A Integrated half-tone screening and enlarging using an enlargement mapping pattern having linked, unique pattern segments Electricity 6 Expired
US8810579B2 Method and apparatus for interactive curve generation Physics 1 Active
US8843455B2 System and method of font compression using selectable entropy encoding Physics 1 Active
US9098524B2 System and method of font compression using selectable entropy encoding Physics 0 Active
US9275018B2 Techniques for analyzing web pages to determine font subsets Physics 0 Active
US8510531B1 Fast, dynamic cache packing Physics 0 Active

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