Resources Contact Us Home
Browse by: INVENTOR PATENT HOLDER PATENT NUMBER DATE
 
 
Coma aberration automatic measuring mark and measuring method










Image Number 2 for United States Patent #6323945.

Two coma aberration automatic measuring marks M1 and M2 of a first-order diffraction grating are each composed of a plurality of elongated isosceles triangle patterns which are so arranged that the axis of symmetry passing on the center of each elongated isosceles triangle is parallel to one another, that a half P1, P2, and P3 of the elongated isosceles triangle patterns have the widths thereof which extend in a direction opposite to that of the remaining half P4, P5 and P6 of the elongated isosceles triangle patterns, and the elongated isosceles triangle patterns are located separately from one another, in a direction perpendicular to the axis of symmetry passing on the center of each elongated isosceles triangle, and at a pitch diffracting a measuring coherent light. The two first-order diffraction gratings M1 and M2 are located separately from each other in a direction of the axis of symmetry passing on the center of the elongated isosceles triangle, in such a manner that the elongated isosceles triangle patterns included in the two first-order diffraction gratings are in symmetry to each other, in connection with a line positioned between the two first-order diffraction gratings and which is perpendicular to the axis of symmetry passing on the center of the elongated isosceles triangle. The two first-order diffraction gratings are scanned by the measuring coherent light, and a relative distance R1 between diffraction lights generated by the two first-order diffraction gratings, is measured and compared with a distance R between the two first-order diffraction gratings.








 
 
  Recently Added Patents
Method for detecting security error in mobile telecommunications system and device of mobile telecommunications
Web development environment that enables a developer to interact with run-time output presentation of a page
Illuminating device
Methods and apparatuses for configuring and operating graphics processing units
Non-phosphorus-based gellant for hydrocarbon fluids
Cable exit trough with insert
Categorization of design rule errors
  Randomly Featured Patents
Differential pressure formed luggage with molded integrated frame
Multipart electronic circuit assembly with detachably interconnecting and locking component circuit substrates
System and method for provisioning a remote resource for an electronic device
Method and apparatus for forming a double walled thermoplastic tube with integral bells
Method for optimizing a web content proxy server and devices thereof
Method and apparatus for encapsulating universal serial bus messaging over link layer communication protocol
Antithrombotic agents
Recombinant animal viral nucleic acids
Computerized gaming system
Humidity sensor element containing polyphenylsulfone