Zeeman atomic absorption spectrophotometer

Claim 2

A Zeeman atomic absorption spectrophotometer comprising: a light source; an atomization section irradiated with the light from said light source including means for atomizing a sample; a detector coupled to receive the light emitted from said light source and then subjected to atomic absorption in said atomization section, and to convert the light into an electric signal; means for generating a pair of Zeeman split light components emitted from the light source including means for applying a magnetic field to the light source; means coupled to the output of said detector for processing the detected signal and producing an atomic absorption signal for the sample, which signal is corrected for background absorption; and means for measuring, during a stage of atomization of the sample in said atomization section, the length of time between an instant at which the intensity of the background absorption-corrected atomic absorption signal initially reaches a predetermined level and an instant at which the intensity of the same signal reaches the same predetermined level for the last time during said stage of atomization.

Claim 3

A Zeeman absorption spectrophotometer according to claim 1, wherein said time measuring means comprises a reference signal source for generating an output of a predetermined level, means for comparing the atomic absorption signal with the reference signal, and a time counter actuated with an output from said comparing means.

Claim 4

A Zeeman atomic absorption spectrophotometer according to claim 1, wherein said time measuring means includes a means for controlling the temperature of said atomization section, said temperature controlling means producing an output signal indicating that the atomization of sample is being carried out.

Claim 5

A Zeeman atomic absorption spectrophotometer according to claim 1, wherein said time measuring means comprises a microprocessor, a random access memory and a read-only memory, said read-only memory memorizing a program comprising a step of successively reading atomic absorption signals during the atomization of the sample, a step of ascertaining that an atomic absorption signal is as high as a predetermined level, a step of successively memorizing an instant at which an atomic absorption signal is as high as a predetermined level, and a step of operating the length of time between an instant at which an atomic absorption signal initially reaches a predetermined level and an instant at which the same signal reaches the same predetermined level for the last time during the atomization stage, said microprocessor being adapted to carry out an operation in accordance with the program by utilizing a memory area in said random access memory.

Claim 6

A Zeeman atomic absorption spectrophotometer according to claim 2, 3 or 4, wherein a plurality of predetermined levels is preset.

Claim 7

A Zeeman atomic absorption spectrophotometer according to claim 2, 3 or 4, wherein the direction in which a magnetic field is applied from said magnetic field applying means is at right angles to an optical axis of the path of said light.

Claim 8

A Zeeman atomic absorption spectrophotometer according to claim 6, wherein the intensity of the magnetic field generated by said magnetic field applying means is constant.

Claim 9

A Zeeman atomic absorption spectrophotometer according to claim 2, 3 or 4, wherein the direction in which a magnetic field is applied from said magnetic field applying means is parallel to the optical axis of the path of said light.

Claim 10

A Zeeman atomic absorption spectrophotometer according to claim 8, wherein the intensity of magnetic field generated by said magnetic field applying means is constant.

Claim 11

A Zeeman atomic absorption spectrophotometer according to claim 1, further comprising a rotating polarizer coupled between the light source and the detector.

Claim 12

A Zeeman atomic absorption spectrophotometer according to claim 1, wherein the time measuring means comprises a reference signal source for generating an output of a predetermined level, means for comparing the atomic absorption signal with the reference signal, and a time counter actuated with an output from said comparing means, and further includes means responsive to the indication signal from the temperature control means for only passing the output of the comparing means to said time counter when the atomization indication signal is present.

Claim 13

A Zeeman atomic absorption spectrophotometer comprising: means for positioning an atomized unknown sample on an optical axis; means positioned along the optical axis to pass light from a light source of a predetermined wavelength through atomic vapors of said atomized sample; means for generating Zeeman split light components emitted from the light source including means for applying a magnetic field to said light source; means for detecting the Zeeman split light components which have passed through the atomic vapors to provide an atomic absorption signal; and means for successively detecting instants t 0 , t 1 . . . t n at which a detected atomic absorption signal attains a predetermined level and for determining the difference between t n and t 0 .

Claim 14

A Zeeman atomic absorption spectrophotometer comprising: means for positioning an atomized unknown sample on an optical axis; means positioned along the optical axis to pass light from a light source of a predetermined wavelength through atomic vapors of said atomized sample; means for generating Zeeman split light components emitted from the light source including means for applying a magnetic field to said light source; means for detecting the Zeeman split light components which have passed through the atomic vapors to provide an atomic absorption signal; and means for successively detecting instants t 0 , t 1 . . . t n at which a detected atomic absorption signal attains a predetermined level and for determining the difference between t n and t 0 .

Claim 15

A Zeeman atomic absorption spectrophotometer according to claim 12, wherein said difference determining mechanism comprises means for comparing the atomic absorption signals with a predetermined value, and a time measuring means actuated by an output from said comparing means.

Claim 16

A Zeeman atomic absorption spectrophotometer according to claim 13, wherein said time measuring means comprises a counter adapted to start a counting operation at instant t 0 , and a latch circuit adapted to latch the content of said counter at the instants t 1 , t 2 . . . t n .

Claim 17

A Zeeman atomic absorption spectrophotometer according to claim 12, wherein said difference determining means comprises a microprocessor, a random access memory, and a read-only memory, said microprocessor operating to fetch atomic absorption signals successively, to judge the atomic absorption signals successively at instants t 0 , t 1 . . . t n , to memorize the instants t 0 , t 1 . . . t n successively in said random access memory, and thereafter to determine the difference between the instants t n and t 0 .

Claim 18

A Zeeman atomic absorption spectrophotometer according to claim 15, wherein said random access memory has two memory areas; and said microprocessor operates to memorize the instant t 0 in a first memory area and renew the content of a second memory area at each of the instants t 1 , t 2 . . . t n .

Claim 19

A Zeeman atomic absorption spectrophotometer according to claim 13 or 15, wherein a plurality of predetermined levels are preset.

Claim 20

A Zeeman atomic absorption spectrophotometer according to claim 13 or 15, wherein the direction in which a magnetic field is applied from said magnetic field applying means is at right angles to the optical axis.

Claim 21

A Zeeman atomic absorption spectrophotometer according to claim 13 or 15, wherein the direction in which a magnetic field is applied from said magnetic field applying means is parallel to the optical axis.

Claim 22

A Zeeman atomic absorption spectrophotometer according to claim 13 or 15, wherein the intensity of magnetic field of said magnetic field applying means is constant.

Claim 23

A Zeeman atomic absorption spectrophotometer comprising: a light source; an atomization section irradiated with the light from said light source including means for atomizing a sample; a detector coupled to receive the light emitted from said light source and then subjected to atomic absorption in said atomization section, and to convert the light into an electric signal; means for generating a pair of Zeeman split components produced in the atomization section including means for applying a magnetic field to the atomization section; means coupled to the output of said detector for processing the detected signal and producing an atomic absorption signal for the sample, which signal is corrected for background absorption; and means for measuring, during a stage of atomization of the sample in said atomization section, the length of time between an instant at which the intensity of the background absorption-corrected atomic absorption signal initially reaches a predetermined level and an instant at which the intensity of the same signal reaches the same predetermined level for the last time during said stage of atomization.

Claim 24

A Zeeman atomic absorption spectrophotometer comprising: a light source; an atomization section irradiated with the light from said light source including means for atomizing a sample; a detector coupled to receive the light emitted from said light source and then subjected to atomic absorption in said atomization section, and to convert the light into an electric signal; means for generating a pair of Zeeman split components produced in the atomization section including means for applying a magnetic field to the atomization section; means coupled to the output of said detector for processing the detected signal and producing an atomic absorption signal for the sample, which signal is corrected for background absorption; and means for measuring, during a stage of atomization of the sample in said atomization section, the length of time between an instant at which the intensity of the background absorption-corrected atomic absorption signal initially reaches a predetermined level and an instant at which the intensity of the same signal reaches the same predetermined level for the last time during said stage of atomization.

Claim 25

A Zeeman atomic absorption spectrophotometer according to claim 21, wherein said time measuring means comprises a reference signal source for generating an output of a predetermined level, means for comparing the atomic absorption signal with the reference signal, and a time counter actuated with an output from said comparing means.

Claim 26

A Zeeman atomic absorption spectrophotometer according to claim 21, wherein said time measuring means include a means for controlling the temperature of said atomization section, said temperature controlling means producing an output signal indicating that the atomization of sample is being carried out.

Claim 27

A Zeeman atomic absorption spectrophotometer according to claim 21, wherein said time measuring means comprises a microprocessor, a random access memory and a read-only memory, said read-only memory memorizing a program comprising a step of successively reading atomic absorption signals during the atomization of the sample, a step of ascertaining that an atomic absorption signal is as high as a predetermined level, a step of successively memorizing an instant at which an atomic absorption signal is as high as a predetermined level, and a step of operating the length of time between an instant at which an atomic absorption signal initially reaches a predetermined level and an instant at which the same signal reaches the same predetermined level for the last time during the atomization stage, said microprocessor being adapted to carry out an operation in accordance with the program by utilizing a memory area in said random access memory.

Claim 28

A Zeeman atomic absorption spectrophotometer according to claim 22, 23 or 24, wherein a plurality of predetermined levels is preset.

Claim 29

A Zeeman atomic absorption spectrophotometer according to claim 22, 23 or 24, wherein the direction in which a magnetic field is applied from said magnetic field applying means is at right angles to an optical axis of the path of said light.

Claim 30

A Zeeman atomic absorption spectrophotometer according to claim 26, wherein the intensity of the magnetic field generated by said magnetic field applying means is constant.

Claim 31

A Zeeman atomic absorption spectrophotometer according to claim 22, 23 or 24, wherein the direction in which a magnetic field is applied from said magnetic field applying means is parallel to the optical axis of the path of said light.

Claim 32

A Zeeman atomic absorption spectrophotometer according to claim 28, wherein the intensity of magnetic field generated by said magnetic field applying means is constant.

Claim 33

A Zeeman atomic absorption spectrophotometer according to claim 21, further comprising a rotating polarizer coupled between the light source and the detector.

Claim 34

A Zeeman atomic absorption spectrophotometer according to claim 21, wherein the time measuring means comprises a reference signal source for generating an output of a predetermined level, means for comparing the atomic absorption signal with the reference signal, and a time counter actuated with an output from said comparing means, and further includes means responsive to the indication signal from the temperature control means for only passing the output of the comparing means to said time counter when the atomization indication signal is present.

Claim 35

A Zeeman atomic absorption spectrophotometer comprising: means for positioning an atomized unknown sample on an optical axis; means positioned along the optical axis to pass light of a predetermined wavelength through atomic vapors of said atomized sample; means for generating Zeeman split light components produced in the atomized sample including means for applying a magnetic field to said atomized sample; means for detecting the light which has passed through the atomic vapors to provide an atomic absorption signal; and means for successively detecting instants t 0 , t 1 . . . t n at which a detected atomic absorption signal attains a predetermined level and for determining the difference between t n and t 0 .

Claim 36

A Zeeman atomic absorption spectrophotometer comprising: means for positioning an atomized unknown sample on an optical axis; means positioned along the optical axis to pass light of a predetermined wavelength through atomic vapors of said atomized sample; means for generating Zeeman split light components produced in the atomized sample including means for applying a magnetic field to said atomized sample; means for detecting the light which has passed through the atomic vapors to provide an atomic absorption signal; and means for successively detecting instants t 0 , t 1 . . . t n at which a detected atomic absorption signal attains a predetermined level and for determining the difference between t n and t 0 .

Claim 37

A Zeeman atomic absorption spectrophotometer according to claim 32, wherein said difference determining mechanism comprises means for comparing the atomic absorption signals with a predetermined value, and a time measuring means actuated by an output from said comparing means.

Claim 38

A Zeeman atomic absorption spectrophotometer according to claim 33, wherein said time measuring means comprises a counter adapted to start a counting operation at instant t 0 , and a latch circuit adapted to latch the content of said counter at the instants t 1 , t 2 . . . t n .

Claim 39

A Zeeman atomic absorption spectrophotometer according to claim 32, wherein said difference determining means comprises a microprocessor, a random access memory, and a read-only memory, said microprocessor operating to fetch atomic absorption signals successively, to judge the atomic absorption signals successively at instants t 0 , t 1 . . . t n , to memorize the instants t 0 , t 1 . . . t n successively in said random access memory, and thereafter to determine the difference between the instants t n and t 0 .

Claim 40

A Zeeman atomic absorption spectrophotometer according to claim 35, wherein said random access memory has two memory areas; and said microprocessor operates to memorize the instant t 0 in a first memory area and renew the content of a second memory area at each of the instants t 1 , t 2 . . . t n .

Claim 41

A Zeeman atomic absorption spectrophotometer according to claim 33 or 35, wherein a plurality of predetermined levels are preset.

Claim 42

A Zeeman atomic absorption spectrophotometer according to claim 33 or 35, wherein the direction in which a magnetic field is applied from said magnetic field applying means is at right angles to the optical axis.

Claim 43

A Zeeman atomic absorption spectrophotometer according to claim 33 or 35, wherein the direction in which a magnetic field is applied from said magnetic field applying means is parallel to the optical axis.

Claim 44

A Zeeman atomic absorption spectrophotometer according to claim 33 or 35, wherein the intensity of magnetic field of said magnetic field applying means is constant.