Claims Analysis
Total Claims: 8
Claim 1
Independent Claim
191 words
Spectrophotometric apparatus for determining substances present in a liquid, comprising: means for emitting luminous radiation in a range from ultraviolet to near infra-red; a monochromator including a grating providing a variable slit width for determining the bandwidth of said luminous radiation; means for focusing said luminous radiation onto the grating of said monochromator; means for exposing the liquid to be examined to said radiation and exposing a known liquid to said radiation for respectively generating first and secOnd spectrums; means for sweeping the spectrum of said luminous radiation by varying the grating of said monochromator; means for alternatively chopping said first and second spectrums; means for analyzing said chopped first and second spectrums to determine the difference therebetween and including an operational amplifier for alternately amplifying said first and second spectrums, said operational amplifier including a feedback circuit with a light generating element for generating a light output proportional to the difference between said first and second spectrums and a light sensitive element responsive to the light output of said light generating means for controlling the resistance of said feedback circuit; and means for recording the output of said operational amplifier.
Claim 2
Dependent Claim
191 words
Spectrophotometric apparatus for determining substances present in a liquid, comprising: means for emitting luminous radiation in a range from ultraviolet to near infra-red; a monochromator including a grating providing a variable slit width for determining the bandwidth of said luminous radiation; means for focusing said luminous radiation onto the grating of said monochromator; means for exposing the liquid to be examined to said radiation and exposing a known liquid to said radiation for respectively generating first and secOnd spectrums; means for sweeping the spectrum of said luminous radiation by varying the grating of said monochromator; means for alternatively chopping said first and second spectrums; means for analyzing said chopped first and second spectrums to determine the difference therebetween and including an operational amplifier for alternately amplifying said first and second spectrums, said operational amplifier including a feedback circuit with a light generating element for generating a light output proportional to the difference between said first and second spectrums and a light sensitive element responsive to the light output of said light generating means for controlling the resistance of said feedback circuit; and means for recording the output of said operational amplifier.
Claim 3
Dependent Claim
56 words
Spectrophotometric apparatus as in claim 1 wherein said means for analyzing further includes first and second inputs, means for switching the input of said operational amplifier to either said first or second input, and means for generating synchronizing pulses to control the switching of said first and second inputs and the operation of said operational amplifier.
Claim 4
Dependent Claim
42 words
Spectrophotometric apparatus as in claim 2 wherein said means for analyzing further includes means for comparing the output of said operational amplifier with a reference voltage and said means for generating light is responsive to the output of said means for comparing.
Claim 5
Dependent Claim
50 words
Spectrophotometric apparatus as in claim 3 wherein said means for switching includes an inverter for generating the ratio of the first input to the second input and the ratio of the second input to the first input and means for switching either of said ratios to said means for comparing.
Claim 6
Dependent Claim
48 words
Spectrophotometric apparatus as in claim 4 wherein said means for switching comprises a pair of symmetrically connected field-effect transistors each having inputs respectively responsive to the input and output of said inverter whereby said first and second inputs are alternatively applied to the input of said operational amplifier.
Claim 7
Dependent Claim
45 words
Spectrophotometric apparatus as in claim 5 wherein said means for comparing includes a symmetrical amplifier and a logic circuit responsive to the output of said symmetrical amplifier and the input and output of said inverter for determining the difference between said first and second inputs.
Claim 8
Dependent Claim
50 words
Spectrophotometric apparatus as in claim 2 wherein said first input receives electrical signals representing recorded output of said operational amplifier and said second input receives electrical signals representing the composition of a known liquid, whereby the output of said operational amplifier indicates the difference between said first and second inputs.