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3660 views
05:39 Feb-02-2004
Ehssein
AT quartz cut

Dear all, I have searched it and I didn't find: what does the appreviation AT means in "AT quartz cut"
Thank you in advance.


 
01:36 Feb-03-2004
Nick Welland
Re: AT quartz cut ----------- Start Original Message -----------
: Dear all, I have searched it and I didn't find: what does the appreviation AT means in "AT quartz cut"
: Thank you in advance.
------------ End Original Message ------------
The "T" means it is a temperature-compensated cut; the orientation is such as to cancel out positive and negative temperature coefficients affecting the vibration frequency, The "A" means it was the first such cut discovered. From memory, the plate is cut parallel to the X crystallographic axis, and inclined at about 35 deg to the Z axis. Quartz is very anisotropic in its properties and there different cuts for various purposes.
Best regards
Nick



 
03:57 Feb-26-2004

Ed Ginzel

R & D, -
Materials Research Institute,
Canada,
Joined Nov 1998
1208
Re: AT quartz cut

Nick: what a good memory you have! The AT cut is indeed 35 degrees from the Z-axis (but parallel to the Y-cut).
I recalled the various cuts being illustrated in an old book I had as an optical mineralogy student, Elements of Mineralogy, by B.Mason and L. Berry, Published by W H Freeman and company, 1968.
I have scanned Figure 4.5 from that text to illustrate the various cuts of oscillator plates that have been cut from quartz crystals.

http://www.ndt.net/wshop/attach/quartz.gif

The quartz crystal was first noted as having piezoelectric properties in 1881 (brothers Curie) but had no applications outside the lab until about 1915 when sonar development began. Later it held importance in radio tuners. Here it waw used with an alternating electrical field applied across the quartz plate. When suitably cut and mounted and dimensioned so that one of its natural frequencies of mechanical vibration matched the resonant frequency of the electrical circuit, the frequency of transmission or receptionwas stabilised or controlled.


----------- Start Original Message -----------
: : Dear all, I have searched it and I didn't find: what does the appreviation AT means in "AT quartz cut"
: : Thank you in advance.
: The "T" means it is a temperature-compensated cut; the orientation is such as to cancel out positive and negative temperature coefficients affecting the vibration frequency, The "A" means it was the first such cut discovered. From memory, the plate is cut parallel to the X crystallographic axis, and inclined at about 35 deg to the Z axis. Quartz is very anisotropic in its properties and there different cuts for various purposes.
: Best regards
: Nick
------------ End Original Message ------------




 
08:09 Feb-28-2004
Nick Welland
Re: AT quartz cut ----------- Start Original Message -----------
: Nick: what a good memory you have! The AT cut is indeed 35 degrees from the Z-axis (but parallel to the Y-cut).
: I recalled the various cuts being illustrated in an old book I had as an optical mineralogy student, Elements of Mineralogy, by B.Mason and L. Berry, Published by W H Freeman and company, 1968.
: I have scanned Figure 4.5 from that text to illustrate the various cuts of oscillator plates that have been cut from quartz crystals.
: http://www.ndt.net/wshop/attach/quartz.gif
: The quartz crystal was first noted as having piezoelectric properties in 1881 (brothers Curie) but had no applications outside the lab until about 1915 when sonar development began. Later it held importance in radio tuners. Here it waw used with an alternating electrical field applied across the quartz plate. When suitably cut and mounted and dimensioned so that one of its natural frequencies of mechanical vibration matched the resonant frequency of the electrical circuit, the frequency of transmission or reception was stabilised or controlled.
:
: : : Dear all, I have searched it and I didn't find: what does the appreviation AT means in "AT quartz cut"
: : : Thank you in advance.
: : The "T" means it is a temperature-compensated cut; the orientation is such as to cancel out positive and negative temperature coefficients affecting the vibration frequency, The "A" means it was the first such cut discovered. From memory, the plate is cut parallel to the X crystallographic axis, and inclined at about 35 deg to the Z axis. Quartz is very anisotropic in its properties and there different cuts for various purposes.
: : Best regards
: : Nick
------------ End Original Message ------------
As always, Ed, your scholarship amazes me. Thanks for the memories! (My text was Kerr's Optical Mineralogy)
Nick


 


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