Digital evaporation monitor system

Claim 2

An evaporation monitoring system comprising: monitor oscillator means including a monitor crystal arranged so that the oscillating frequency of said oscillator means varies in accordance with the amount of vapor deposited upon said crystal; counting means arranged to count and store digital counts therein with said counting means including means for storing a preselected digital count selected in accordance with the desired amount of vapor to be deposited upon said crystal; and circuit means coupling said monitor oscillator means to said counting means, said circuit means arranged to combine signals indicative of the initial frequency of said oscillator means with said preselected count in said counting means so as to provide a combined count therein which is the sum of said preselected count and the count of said initial frequency, said circuit means including means for thereafter periodically comparing the frequency count of said oscillator means as it changes in accordance with the amount of vapor deposited upon said crystal, with said combined count so as to thereby provide an indication of the amount of vapor deposited upon said crystal.

Claim 3

An evaporation monitoring system comprising: monitor oscillator means including a monitor crystal which varies the oscillating frequency of said oscillator from an initial frequency in accordance with the amount of vapor deposited thereon; counting means arranged to store a preselected digital count therein, said count being selected in accordance with the desired amount of vapor to be deposited upon said monitor crystal; circuit means coupling said monitor oscillator means to said counting means for a preselected interval of time so that the frequency count of the said initial frequency of said monitor oscillator means is combined with the said preselected count in said counting means to provide a combined count which is the sum of said frequency count and said preselected count; compare circuit means; and means including said counting means coupled to said compare circuit means to provide for the repetitive comparing of the frequency count of said monitor oscillator means, as it varies from said initial frequency in response to the vapor deposited, with the said combined count until the frequency count of said monitor oscillator means compares with the said combined count.

Claim 4

An evaporation monitoring system comprising: monitor oscillator means including a monitor crystal which varies the oscillating frequency of said oscillator from an initial frequency in accordance with the amount of vapor deposited thereon; counting means arranged to store a preselected digital count therein, said count being selected in accordance with the desired amount of vapor to be deposited upon said monitor crystal; circuit means coupling said monitor oscillator means to said counting means for a preselected interval of time so that the frequency count of the said initial frequency of said monitor oscillator means is combined with the said preselected count in said counting means to provide a combined count which is the sum of said frequency count and said preselected count; compare circuit means; and means including said counting means coupled to said compare circuit means to provide for the repetitive comparing of the frequency count of said monitor oscillator means, as it varies from said initial frequency in response to the vapor deposited, with the said combined count until the frequency count of said monitor oscillator means compares with the said combined count.

Claim 5

The system as set forth in claim 2 further including, means to indicate the difference count between the frequency count of said monitor oscillator means and said combined count, said difference count being indicative of the thickness of vapor deposited upon said monitor crystal.

Claim 6

The system as set forth in claim 3 further including, count means arranged to be incremented in accordance with the prevailing count of the frequency of said monitor oscillator means taken over a set interval of time and, at a preselected time thereafter, to be decremented in accordance with the then prevailing count of the frequency of the said monitor oscillator means taken over said set interval of time.

Claim 7

An evaporation monitoring system comprising: monitor oscillator means including a crystal arranged so that the oscillating frequency of said monitor oscillator means varies from an initial frequency in accordance with the amount of vapor deposited upon said crystal; counting means arranged to count and store a digital count; means coupled to said counting means to enter a preselected count therein indicative of the amount of vapor to be deposited upon said crystal; circuit means coupling said monitor oscillator means to said counting means so as to add the frequency count of the said initial frequency of said monitor oscillator means to the said preselected count in said counting means to provide an initial combined count, and to thereafter compare the frequency count of said monitor oscillator means, as it varies in accordance with the amount of vapor deposited upon said crystal, to said combined count until a compare is reached.

Claim 8

An evaporation monitoring system comprising: monitor oscillator means including a crystal arranged so that the oscillating frequency of said monitor oscillator means varies from an initial frequency in accordance with the amount of vapor deposited upon said crystal; counting means arranged to count and store a digital count; means coupled to said counting means to enter a preselected count therein indicative of the amount of vapor to be deposited upon said crystal; circuit means coupling said monitor oscillator means to said counting means so as to add the frequency count of the said initial frequency of said monitor oscillator means to the said preselected count in said counting means to provide an initial combined count, and to thereafter compare the frequency count of said monitor oscillator means, as it varies in accordance with the amount of vapor deposited upon said crystal, to said combined count until a compare is reached.

Claim 9

In an evaporation monitoring system including a reference oscillator means and a monitor oscillator means, said monitor oscillator means having a crystal which varies the oscillating frequency of said monitor oscillator means accordance with the thickness of evaporation thereon comprising; presetable counter means having a preselected count therein; circuit means including means coupled to said monitor oscillator and said presetable counter means to effect the initial sampling of the frequency count on said monitor oscillator means and add the sampled frequency count to said preselected count in said presetable counter means to provide a combined count therein; compare circuit means; control means coupled to said circuit means and said compare circuit means to control said circuit means to effect the periodic sampling of the count on said monitor oscillator means, as said frequency count varies in accordance with the thickness of evaporation on said crystal, and to compare in said compare circuit means the said periodic sample of the count with said combined count; and indicator means coupled to indicate the difference between the periodically sampled count on said monitor oscillator means and said combined count, said difference being indicative of the evaporation thickness on said crystal.

Claim 10

In an evaporation monitoring system including a reference oscillator means and a monitor oscillator means, said monitor oscillator means having a crystal which varies the oscillating frequency of said monitor oscillator means accordance with the thickness of evaporation thereon comprising; presetable counter means having a preselected count therein; circuit means including means coupled to said monitor oscillator and said presetable counter means to effect the initial sampling of the frequency count on said monitor oscillator means and add the sampled frequency count to said preselected count in said presetable counter means to provide a combined count therein; compare circuit means; control means coupled to said circuit means and said compare circuit means to control said circuit means to effect the periodic sampling of the count on said monitor oscillator means, as said frequency count varies in accordance with the thickness of evaporation on said crystal, and to compare in said compare circuit means the said periodic sample of the count with said combined count; and indicator means coupled to indicate the difference between the periodically sampled count on said monitor oscillator means and said combined count, said difference being indicative of the evaporation thickness on said crystal.

Claim 11

The system as set forth in claim 6 wherein said indicator means includes means to indicate the rate of evaporation.

Claim 12

An evaporation monitoring system comprising; monitor oscillator means including a crystal arranged so that the oscillating frequency of said oscillator means varies in accordance with the amount of vapor deposited upon said crystal; presetable counter means; means coupled to said presetable counter means to preset said presetable counter means to a preselected count, said preselected count being indicative of the desired amount of vapor to be deposited upon said crystal; control circuit means coupling said monitor oscillator means to said presetable counter means; means coupled to said control circuit means to cause the initial frequency count on said monitor oscillator means to be added to the preselected count in said presetable counter means to thereby provide a combined count in said presetable counter means; means including storage means coupled to said presetable counter means to cause the combined count in said presetable counter means to be transferred to said storage means; compare circuit means coupled to said means including storage means and to Said presetable counter means; further means coupled to said control circuit means for periodically causing the frequency count on said monitor oscillator means, as it varies in accordance with the amount of vapor deposited upon said crystal, to be counted by said presetable counter means and compared with the combined count stored in said storage means; and reference oscillator means coupled to said presetable counter means to add to count to said presetable counter means required to make the frequency count on said monitor oscillator means compare with the combined count stored in said storage means, said added count being related to the amount of vapor deposited upon said crystal.

Claim 13

An evaporation monitoring system comprising; monitor oscillator means including a crystal arranged so that the oscillating frequency of said oscillator means varies in accordance with the amount of vapor deposited upon said crystal; presetable counter means; means coupled to said presetable counter means to preset said presetable counter means to a preselected count, said preselected count being indicative of the desired amount of vapor to be deposited upon said crystal; control circuit means coupling said monitor oscillator means to said presetable counter means; means coupled to said control circuit means to cause the initial frequency count on said monitor oscillator means to be added to the preselected count in said presetable counter means to thereby provide a combined count in said presetable counter means; means including storage means coupled to said presetable counter means to cause the combined count in said presetable counter means to be transferred to said storage means; compare circuit means coupled to said means including storage means and to Said presetable counter means; further means coupled to said control circuit means for periodically causing the frequency count on said monitor oscillator means, as it varies in accordance with the amount of vapor deposited upon said crystal, to be counted by said presetable counter means and compared with the combined count stored in said storage means; and reference oscillator means coupled to said presetable counter means to add to count to said presetable counter means required to make the frequency count on said monitor oscillator means compare with the combined count stored in said storage means, said added count being related to the amount of vapor deposited upon said crystal.

Claim 14

The system as set forth in claim 8 further including up-down counter means coupling both said monitor oscillator means and said reference oscillator means to display means, said up-down counter means acting to provide digital signals to said display means to thereby produce an indication of both thickness and rate of evaporation.

Claim 15

The system as set forth in claim 9 wherein said monitor oscillator means includes a local oscillator, a monitor oscillator and a mixer coupled to said local oscillator and to said monitor oscillator, said local oscillator having a frequency greater than the frequency of said monitor oscillator so that the difference frequency from said mixer increases with increases in the amount of vapor deposited upon said crystal during a first phase of operation when the frequency count on said monitor oscillator is being compared to the said combined count in said storage means to thereby provide an indication of the amount of vapor deposited upon said crystal.

Claim 16

The system as set forth in claim 10 wherein said monitor oscillator means further includes an additional local oscillator coupled to said mixer, said additional local oscillator having a frequency less than the frequency of said monitor oscillator so that the difference frequency from said mixer decreases with increases in the amount of vapor deposited upon said crystal during a second phase of operation when the frequency count on said monitor oscillator is being added to, and then subtracted from, said up-down counter means over respective fixed intervals of time to thereby provide an indication of the rate at which vapor is being deposited upon said crystal.