Patent ID: 6744182
Filing Date: 2004-06-01
Classification: H03H,Y10T

Abstract:
A piezoelectric quartz plate having reduced frequency deviation as a function of temperature, wherein said plate is cut at an angle described by: Tf=3.9+6.5&it;cos2&it;Î¸+12&af;[c66&it;Tc66&it;sin2&it;Î¸+c44&it;Tc44&it;cos2&it;Î¸+Tc14&it;c14&it;sin&it;â€ƒ&it;2&it;Î¸c66&it;sin2&it;Î¸+c44&it;cos2&it;Î¸+c14&it;sin&it;â€ƒ&it;2&it;Î¸]+&AutoLeftMatch;[aâ€²&CenterDot;(sin&it;(Ï‰&CenterDot;Î¸+Ï†â€²)+(sin&it;(Ï‰&CenterDot;Î¸+Ï†â€²))2)]+Î´whereTf=frequency temperature coefficient, &thgr;=angle of rotation from the Z axis, cxx=is the value of stiffness, the subscripts denote the stiffness of a given rhombohedral axis, &ohgr;=the angular velocity of the wave traversing the crystal face, aâ€²=the amplitude of the wave traversing the crystal face, &phgr;â€²=the phase delay imposed on the wave traversing the crystal face due to resistance by its surroundings, and &dgr;=offset value between the idealized wave and the wave with a damping function; wherein the angle of cut is from âˆ’90 to 0.26 degrees, 0.26 to 29.74 degrees, 30.26 to 69.74 degrees and 70.26 to 90 degrees in phi.