Microwave oven window

An observation window, for a microwave device exhibiting microwave radiation of a predetermined frequency, the observation window comprising:

• a first transparent panel having a first major surface and a second major surface opposing said first major surface, said first transparent panel having a first predetermined thickness defining the distance between the first major surface and the second major surface thereof,
• said first major surface of said first transparent panel having a first optically transparent conductive film, which primarily reflects incident microwave radiation, applied thereto, and
• said second major surface of said first transparent panel not exhibiting an optically transparent conductive film, which primarily reflects incident microwave radiation, applied thereto;
• and
• a second transparent panel having a first major surface and a second major surface opposing said first major surface, said second transparent panel having a second predetermined thickness defining the distance between the first major surface and the second major surface thereof,
• said first major surface of said second transparent exhibiting a second optically transparent conductive film, which primarily reflects incident microwave radiation, applied thereto, and
• said second major surface of said second transparent panel not exhibiting an optically transparent conductive film which primarily reflects incident microwave radiation, applied thereto;
• and
• a third transparent panel having a first major surface and a second major surface opposing said first major surface and a third predetermined thickness defining the distance between the first major surface and the second major surface of the third transparent panel,
• wherein said second major surface of said first transparent panel abuts the first major surface of said third transparent panel and said second major surface of said second transparent panel abuts the second major surface of said third transparent panel such that the first optically transparent conductive film is substantially parallel with the second optically transparent conductive film, the combination of the first predetermined thickness, the second predetermined thickness and the third predetermined thickness defines a predetermined spatial separation of the first optically transparent conductive film from the second optically transparent conductive film, said predetermined spatial separation defining an interstice,
• said predetermined spatial separation being equal to an odd integer multiple of one quarter of the wavelength of the microwave radiation of the predetermined frequency in the interstice between said first and second transparent conductive films, said predetermined distance having a tolerance of plus or minus 0.15 of said wavelength in the interstice.

An observation window for a microwave device exhibiting microwave radiation of a predetermined frequency, the observation window comprising:

• a first transparent panel having a first major surface and a second major surface opposing said first major surface,
• said first major surface of said first transparent panel having a first optically transparent conductive film, which primarily reflects incident microwave radiation, applied thereto, and
• said second major surface of said first transparent panel not exhibiting an optically transparent conductive film, which primarily reflects incident microwave radiation, applied thereto;
• and
• a second transparent panel having a first major surface and a second major surface opposing said first major surface,
• said first major surface of said second transparent exhibiting a second optically transparent conductive film, which primarily reflects incident microwave radiation, applied thereto, and
• said second major surface of said second transparent panel not exhibiting an optically transparent conductive film which primarily reflects incident microwave radiation, applied thereto;
• and
• a third transparent panel having a first major surface and a second major surface opposing said first major surface and a predetermined thickness defining the distance between the first major surface and the second major surface of the third transparent panel,
• wherein said first major surface of said first transparent panel abuts the first major surface of said third transparent panel and said first major surface of said second transparent panel abuts the second major surface of said third transparent panel opposing said first major face of said third transparent panel, such that the first optically transparent conductive film is substantially parallel with the second optically transparent conductive film, and the predetermined thickness of said third transparent panel defines a predetermined spatial separation of the first optically transparent conductive film from the second optically transparent conductive film, said predetermined spatial separation defining an interstice,
• said predetermined spatial separation being equal to an odd integer multiple of one quarter of the wavelength of the microwave radiation of the predetermined frequency in the interstice between said first and second transparent conductive films, said predetermined distance having a tolerance of plus or minus 0.15 of said wavelength in the interstice.