| 摘要 |
"Optical measuring device that comprises a graduated scale (2) with an incremental track and an absolute track, and a detection unit that comprises means for measuring a relative position which comprise a first photoemitter (6), a sensing graticule (7) and photodetector means (8), and means for measuring an absolute position that comprise a second photoemitter (9) and a linear sensor of photodetectors (11). The detection unit comprises a positioning module (10) that has, attached to it by adhesive means (20), a support piece (30) in which the sensing graticule (7) and the linear sensor of photodetectors (11) are arranged. The physical characteristics of the support piece (30), the adhesive means (20) and the positioning module (10) are such that the equivalent thermal expansion coefficient (± 30e ) of the support piece (30) is substantially the same as the thermal expansion coefficient (± 2 ) of the graduated scale (2)."
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