Patents Assigned to Sony Precision Technology
  • Patent number: 7034948
    Abstract: A displacement pickup is provided which includes a displaceable scale (12) having defined therein a first area (12a) where positional information is recorded with a predetermined pitch and a second area (12b) where positional information is recorded with a predetermined pitch different from that in the first area (12a), a first reading system (10) to read the positional information recorded in the first area (12a), a first phase detector (14) to detect a first phase on the basis of the positional information read by the first reading system (10), a second reading system (11) to read the positional information recorded in the second area (12b), a second phase detector (15) to detect a second phase on the basis of the positional information read by the second reading system (11), a phase comparator (16) to make a comparison between the first and second phases, and an origin signal generator (17) to generate an origin signal according to the result of comparison from the phase comparator (16).
    Type: Grant
    Filed: October 22, 2003
    Date of Patent: April 25, 2006
    Assignee: Sony Precision Technology
    Inventors: Hideaki Tamiya, Kayoko Taniguchi, Akihiro Kuroda
  • Publication number: 20040080755
    Abstract: A displacement pickup is provided which includes a displaceable scale (12) having defined therein a first area (12a) where positional information is recorded with a predetermined pitch and a second area (12b) where positional information is recorded with a predetermined pitch different from that in the first area (12a), a first reading system (10) to read the positional information recorded in the first area (12a), a first phase detector (14) to detect a first phase on the basis of the positional information read by the first reading system (10), a second reading system (11) to read the positional information recorded in the second area (12b), a second phase detector (15) to detect a second phase on the basis of the positional information read by the second reading system (11), a phase comparator (16) to make a comparison between the first and second phases, and an origin signal generator (17) to generate an origin signal according to the result of comparison from the phase comparator (16).
    Type: Application
    Filed: October 22, 2003
    Publication date: April 29, 2004
    Applicant: Sony Precision Technology
    Inventors: Hideaki Tamiya, Kayoko Taniguchi, Akihiro Kuroda