Resources Contact Us Home
Browse by: INVENTOR PATENT HOLDER PATENT NUMBER DATE
 
 
Objective lens, optical element, optical pick-up apparatus and optical information recording and/or reproducing apparatus equipped therewith










Image Number 13 for United States Patent #7483358.

A hybrid objective lens has a refractive lens and a diffractive optical element constructed by plural coaxial ring-shaped zones on at least one optical surface thereof. When n1, n2 and n3 each is a diffraction order of a diffracted ray having a maximum light amount among diffracted rays of each of first, second and third light flux having wavelength .lamda.1, .lamda.2 and .lamda.3 when respective light flux comes to be incident into the diffractive structure respectively, the following formulas are satisfied: |n1|>|n2|, and |n1>|n3 |, and the hybrid objective lens converges a n1-th, n2-th and N3-th order diffracted ray of the first, second and third light flux onto an information recording plane of each of the first, second ant third optical information recording medium respectively so as to form an appropriate wavefront within respective prescribed necessary image side numerical apertures.








 
 
  Recently Added Patents
Pharmaceutical dosage form
Female urine funnel
Geographically self-labeling access points
Optical packet signal transmission device and WDM optical communication network
OFDM control signaling in the presence of timing asynchronization in a peer-to-peer network
System of providing an internet web site that assists medical professionals draft a letter of medical necessity or other documentation for transmission to a third party payer on behalf of a pa
End-of-session authentication
  Randomly Featured Patents
System for measuring the torque applied to a threaded connection between sections of oilfield pipe
Insignia positioning device
Contact insertion and wire lay robotic end effector apparatus
Epicyclic transmission utilizing sets of races having differential clearances
Vibration motor
Power inverter having series connection of semiconductor devices each having an inverse parallel connection of an insulated gate bipolar transistor and a diode
Television browsing system with transmitted and received keys and associated information
Control device for the throughput in a conduit portion or similar
Manufacturing method of semiconductor device
Corksrew