Method of measuring the rate of evaporation in a vacuum,a gauge for carrying this method into effect,and an application of this method

Claim 2

A method according to claim 1, which comprises using the inelastic collisions of the electrons of said beam, the collision products that are collected being ions which are generated within said vapor jet by said beam, so that said current is an ionic current.

Claim 3

A method according to claim 1, which comprises using the elastic collisions of the electrons of said beam, the collision products that are collected being electrons of said beam which are scattered by said vapor jet, so that said current is an electronic current.

Claim 4

A method according to claim 1, which comprises imparting to said electronic beam a rectilinear scanning action, said scanned surface being a portion of a plane through which passes said vapor jet.

Claim 5

A method according to claim 1, which comprises imparting to said electronic beam a circular scanning action, said scanned surface being a conical revolution surface through which passes said vapor jet.

Claim 6

A gauge for measuring, by means of an electronic beam, the rate of evaporation of substances which are vaporized in the form of at least one jet of vapor in an evacuated enclosure, which comprises: a. an electron source comprising an electron gun constructed to generate a sharp electronic beam, a deflecting device located at the outlet of said electron gun, and a scanning generator for controlling said deflecting device for moving said sharp electronic beam along a scanning surface having as its axis of symmetry the axis of the electron gun; b. an electron collector located, in relation to the vapor jet, on the side opposite the electron source; c. a collision products collector placed away from said scanning surface for collecting the collision products generated by said electron beam along its path; d. at least one measuring instrument; and e. a detection circuit, connecting said collision products collector to said measuring instrument, comprising means for eliminating the continuous component of the current circulating in said collector under the effect of the collected collision products and means for transmitting to said measuring instrument only the periodic component of said current so that said measuring instrument is insensitive to the collision products generated in the residual gas present in said enclosure but sensitive only to the collision products generated in said vapor jet.

Claim 7

A gauge according to claim 7; wherein said collision products collector has imparted thereto, in relation to said electron collector, a negative potential, so that the collision products it collects are ions generated by inelastic collisions of the electrons of said electronic beam.

Claim 8

A gauge according to claim 7, wherein said collision products collector has imparted thereto, in relation to said electron collector, a positive potential, so that the collision products it collects are electrons scattered through elastic collision of the electrons of said electronic beam.

Claim 9

A gauge according to claim 7, wherein said deflecting device has a rectilinear scanning action so that said electronic beam scans a portion of a plane through which passes said vapor jet.

Claim 10

A gauge according to claim 7, wherein said deflecting device has a circular scanning action, so that said electronic beam scans a conical revolution surface whose axis meats said vapor jet and through which passes the latter.

Claim 11

A gauge according to claim 10, wherein the substances are vaporized in the form of at least two vapor jets and wherein said detection circuit comprises a plurality of different channels, equal in number to that of the jets, and a synchronous electronic switching system for cyclically feeding the current circulating in said collision products collector to each of said channels, said switching system being so controlled by said scanning generator that the succession of channels receiving the current due to the collision products is identical to the succession of vapor jets encountered by said electronic beam, so that said gauge will successively measure the rate of evaporation within several vapor jets.

Claim 12

A gauge according to claim 7, wherein said electron collector is connected to a regulator for regulating the current emitted by said electron gun to allow the intensity of said electronic beam to be tied to a constant value.

Claim 13

A gauge according to claim 10, wherein the scanning voltage supplied by said generator has a rectangular wave shape so that said sharp electronic beam alternately oscillates in said plane portion from a first position, in which it passes to the side of said jet of vapor to a second position, in which it crosses said jet of vapor, the cross section of the latter in said plane portion having the shape of a curvilinear trapezium having two parallel sides that are concentric arcs centered on the point of oscillation of said electronic beam and two other sides that are radial in relation to these arcs.