Non-coherent multi-channel optical spectrum analyzer

Claim 2

Apparatus for analyzing the frequency content of an electrical input signal comprising: electronic display means connected to said input signal for converting said input signal into an intensity modulated optical signal; means for projecting said optical signal; movable photo-sensitive recording means for recording said projected optical signals at a preselected speed for providing a time base for said recording; means for generating a plurality of optical reference signals, each of said optical reference signals being representative of a different particular frequency within a preselected frequency band; means for comparing the frequency of said optical signal with said reference signals; means responsive to said comparison means for detecting coincidence of frequency of said optical signal with the frequency of any of said reference signals; and means for determining the frequency of the reference signals coinciding with said optical signals.

Claim 3

Apparatus for analyzing the frequency content of an electrical signal comprising: means for converting the electrical input signal to an optical signal having the same frequency content as said input signal; a light source; a circular transparent reference frequency mask having an opaque pattern on the surface thereof representative of a preselected frequency band; a plate having a slit-like opening and mounted adjacent said mask on the opposite side from said light source and arranged such that said opening lies along a radial line with respect to said mask; means for rotating said mask at a predetermined rate; means for determining the instantaneous angular position of said mask with respect to said opening; means for projecting light from said source through said mask and said opening whereby the light projected through said slit is modulated by said rotating pattern and is projected as a series of lines extending across said opening and varying from a minimum to a maximum number of lines representative of the preselected frequency band; means for comparing the frequency of said optical signal with said reference signals; means responsive to said comparison means for detecting coincidence of frequency of said optical signal with the frequency of any of said reference signals; and means for determining the frequency of the reference signals coinciding with said optical signals.

Claim 4

Apparatus for analyzing the frequency content of an electrical signal comprising: means for converting the electrical input signal to an optical signal having the same frequency content as said input signal; a light source; a circular transparent reference frequency mask having an opaque pattern on the surface thereof representative of a preselected frequency band; a plate having a slit-like opening and mounted adjacent said mask on the opposite side from said light source and arranged such that said opening lies along a radial line with respect to said mask; means for rotating said mask at a predetermined rate; means for determining the instantaneous angular position of said mask with respect to said opening; means for projecting light from said source through said mask and said opening whereby the light projected through said slit is modulated by said rotating pattern and is projected as a series of lines extending across said opening and varying from a minimum to a maximum number of lines representative of the preselected frequency band; means for comparing the frequency of said optical signal with said reference signals; means responsive to said comparison means for detecting coincidence of frequency of said optical signal with the frequency of any of said reference signals; and means for determining the frequency of the reference signals coinciding with said optical signals.

Claim 5

Apparatus for simultaneously analyzing the frequency content of a plurality of electrical signals comprising: electronic display means connected to said electrical signals for optically displaying said electrical signals; means connected to said electrical signals and said display means for causing said electrical signals to appear on said display means as unique optical signals density modulated according to the frequency of said electrical signals; means for projecting said optical signals to a continuously moving, photo-sensitive film such that each of said optical signals appears on said film as a separate density modulated track; means for generating a plurality of optical reference signals, each of said signals being of a different frequency within a preselected frequency band; means for simultaneously comparing each of said optical signals with said optical reference signals; means for determining coincidence of frequency between said optical signals and said optical reference signals and generating an electrical output in response thereto; and means for determining the frequency of the optical signals coinciding with frequencies of said optical signals.

Claim 6

Apparatus for simultaneously analyzing the frequency content of a plurality of electrical signals comprising: electronic display means connected to said electrical signals for optically displaying said electrical signals; means connected to said electrical signals and said display means for causing said electrical signals to appear on said display means as unique optical signals density modulated according to the frequency of said electrical signals; means for projecting said optical signals to a continuously moving, photo-sensitive film such that each of said optical signals appears on said film as a separate density modulated track; means for generating a plurality of optical reference signals, each of said signals being of a different frequency within a preselected frequency band; means for simultaneously comparing each of said optical signals with said optical reference signals; means for determining coincidence of frequency between said optical signals and said optical reference signals and generating an electrical output in response thereto; and means for determining the frequency of the optical signals coinciding with frequencies of said optical signals.

Claim 7

Apparatus for simultaneously analyzing the frequency content of a plurality of electrical signals comprising: means for converting said electrical signals to optical signals having the same frequency content as said electrical signals; a light source; a circular transparent reference frequency mask having an opaque pattern on the surface thereof representative of a preselected frequency band; a plate having a slit-like opening and mounted adjacent said mask on the opposite side from said light source and arranged such that said opening lies along a radial line with respect to said mask; means for rotating said mask at a predetermined rate; means for determining the instantaneous angular position of said mask with respect to said opening; means for projecting light from said source through said mask and said opening whereby the light projected through said slit is modulated by said rotating pattern and is projected as a series of lines extending across said opening and varying from a minimum to a maximum number of lines representative of the prEselected frequency band; means for simultaneously comparing each of said optical signals with said optical reference signals; means for determining coincidence of frequency between said optical signals and said optical reference signals and generating an electrical output in response thereto; and means for determining the frequency of the optical signals coinciding with frequencies of said optical signals.

Claim 8

Apparatus for simultaneously analyzing the frequency content of a plurality of electrical signals comprising: means for converting said electrical signals to optical signals having the same frequency content as said electrical signals; a light source; a circular transparent reference frequency mask having an opaque pattern on the surface thereof representative of a preselected frequency band; a plate having a slit-like opening and mounted adjacent said mask on the opposite side from said light source and arranged such that said opening lies along a radial line with respect to said mask; means for rotating said mask at a predetermined rate; means for determining the instantaneous angular position of said mask with respect to said opening; means for projecting light from said source through said mask and said opening whereby the light projected through said slit is modulated by said rotating pattern and is projected as a series of lines extending across said opening and varying from a minimum to a maximum number of lines representative of the prEselected frequency band; means for simultaneously comparing each of said optical signals with said optical reference signals; means for determining coincidence of frequency between said optical signals and said optical reference signals and generating an electrical output in response thereto; and means for determining the frequency of the optical signals coinciding with frequencies of said optical signals.