Vacuum-tight window arrangement for rectangular waveguides

Claim 2

A vacuum-tight window arrangement for high power transit time tubes operating in the mm range, comprising: a rectangular waveguide center element containing a one-piece rectangular dielectric window which is permeable to waves and having a thickness which corresponds to approximately λ o /2 .√ε of the center-frequency passing through the window, a pair of rectangular apertures on opposite sides of said window, the elements related by the combined expressions 0.4<1/a<0.6, ##EQU1## 0.65<a'/a<0.85, where 1 is the distance between said window and each aperture, a is the internal width of said waveguide, d B is the thickness of the an aperture, λ o is the wavelength of the center frequency, ε is the dielectric constant of the material of the window, and a' is the internal waveguide width at the apertures.

Claim 3

The window arrangement of claim 1, wherein the relationship 1<λ o /2 holds true.

Claim 4

The window arrangement of claim 1, comprising: a rectangular waveguide center element containing said window, a cylindrical housing mounting said center element and including said pair of rectangular apertures in the ends of said housing and comprising a cup-shaped member including an end wall having one of said apertures therein, and a disc-shaped member having the other aperture therein disposed in the open end of said cup-shaped member.

Claim 5

The window arrangement of claim 3, wherein each of said housing members includes a recess adjacent the respective aperture receiving a respective end of said center element.

Claim 6

The window arrangement of claim 1, wherein the combined expressions are more specifically 0.46<1/a<0.53, ##EQU2## 0.75<a'/a<0.8.

Claim 7

The vacuum-tight window arrangement of claim 5, wherein said rectangular waveguide is spaced from the inner surface of said side wall forming a coolant chamber therebetween.

Claim 8

The vacuum-tight window arrangement of claim 5, wherein the cross-sectional dimensions of said waveguide and said apertures transverse to a and a' are equal.

Claim 9

The vacuum-tight window arrangement of claim 5, wherein said waveguide comprises copper.

Claim 10

A vacuum-tight window arrangement for high power transit time tubes, comprising: a cup-shaped member including a cylindrical side wall and an end wall; a disc-shaped member sealed to said cylindrical side wall opposite said end wall; a pair of rectangular apertures aligned with each other and located in said end wall and said disc-shaped member respectively; a pair of rectangular recesses aligned with each other and located about respective ones of said apertures; a rectangular waveguide having a pair of ends, each of said ends disposed in a respective recess and sealed to said end wall and said disc-shaped member, respectively; a dielectric window mounted sealed within and across said rectangular waveguide; said window having a thickness of approximately λ o /2 .√ε of the center frequency dimensioned according to the relationships 0.4<1/a<0.6, ##EQU3## 0.65<a'/a<0.85, where 1 is the distance between said window and each aperture, a is the internal width of the waveguide, d B is the thickness of an aperture, λ o is the wavelength of the center frequency, ε is the dielectric constant of the material of the window, and a' is the internal width of the waveguide at an aperture.

Claim 11

A vacuum-tight window arrangement for high power transit time tubes, comprising: a cup-shaped member including a cylindrical side wall and an end wall; a disc-shaped member sealed to said cylindrical side wall opposite said end wall; a pair of rectangular apertures aligned with each other and located in said end wall and said disc-shaped member respectively; a pair of rectangular recesses aligned with each other and located about respective ones of said apertures; a rectangular waveguide having a pair of ends, each of said ends disposed in a respective recess and sealed to said end wall and said disc-shaped member, respectively; a dielectric window mounted sealed within and across said rectangular waveguide; said window having a thickness of approximately λ o /2 .√ε of the center frequency dimensioned according to the relationships 0.4<1/a<0.6, ##EQU3## 0.65<a'/a<0.85, where 1 is the distance between said window and each aperture, a is the internal width of the waveguide, d B is the thickness of an aperture, λ o is the wavelength of the center frequency, ε is the dielectric constant of the material of the window, and a' is the internal width of the waveguide at an aperture.

Claim 12

The vacuum-tight window arrangement of claim 9, wherein said window is a BeO window and the dimensioning relationships are more specifically defined as 0.46<1/a<0.53, ##EQU4## 0.75<a'/a<0.8.