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An optical measuring device generates a plurality of measured optical data from inspection of a thin film stack. The measured optical data group naturally into several domains. In turn the thin film parameters associated with the data fall into two categories: local and global. Local "genes" represe

An optical measuring device generates a plurality of measured optical data from inspection of a thin film stack. The measured optical data group naturally into several domains. In turn the thin film parameters associated with the data fall into two categories: local and global. Local "genes" represent parameters that are associated with only one domain, while global genes represent parameters that are associated with multiple domains. A processor evolves models for the data associated with each domain, which models are compared to the measured data, and a "best fit" solution is provided as the result. Each model of theoretical data is represented by an underlying "genotype" which is an ordered set of the genes. For each domain a "population" of genotypes is evolved through the use of a genetic algorithm. The global genes are allowed to "migrate" among multiple domains during the evolution process. Each genotype has a fitness associated therewith based on how much the theoretical data predicted by the genotype differs from the measured data. During the evolution process, individual genotypes are selected based on fitness, then a genetic operation is performed on the selected genotypes to produce new genotypes. Multiple generations of genotypes are evolved until an acceptable solution is obtained or other termination criterion is satisfied.

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An optical measuring device generates a plurality of measured optical data from inspection of a thin film stack. The measured optical data group naturally into several domains. In turn the thin film parameters associated with the data fall into two categories: local and global. Local "genes" represe

An optical measuring device generates a plurality of measured optical data from inspection of a thin film stack. The measured optical data group naturally into several domains. In turn the thin film parameters associated with the data fall into two categories: local and global. Local "genes" represent parameters that are associated with only one domain, while global genes represent parameters that are associated with multiple domains. A processor evolves models for the data associated with each domain, which models are compared to the measured data, and a "best fit" solution is provided as the result. Each model of theoretical data is represented by an underlying "genotype" which is an ordered set of the genes. For each domain a "population" of genotypes is evolved through the use of a genetic algorithm. The global genes are allowed to "migrate" among multiple domains during the evolution process. Each genotype has a fitness associated therewith based on how much the theoretical data predicted by the genotype differs from the measured data. During the evolution process, individual genotypes are selected based on fitness, then a genetic operation is performed on the selected genotypes to produce new genotypes. Multiple generations of genotypes are evolved until an acceptable solution is obtained or other termination criterion is satisfied. of digital samples. 5. The measurement system of claim 4, wherein said controller comprises one of a programmed computing device and an application specific integrated circuit. 6. The measurement system of claim 3, wherein the light from an object passing through the field of view is scattered by that object, producing scattered light that is directed by the optical element along the collection path. 7. The measurement system of claim 3, wherein the light from an object passing through the field of view comprises an unstimulated emission from said object. 8. The imaging system of claim 3, wherein the light from an object passing through the field of view comprises a stimulated emission from said object. 9. The measurement system of claim 3, wherein said means for converting the electrical signal into a sequence of digital samples comprises: (a) an amplifier having an input that is coupled to the detector and an output, said amplifier amplifying the electrical signal, producing an amplified electrical signal at its output; (b) a bandpass filter coupled to the output of the amplifier, said bandpass filter filtering the amplified electrical signal to produce a passband signal; and (c) an analog-to-digital converter that converts the passband signal to the sequence of digital samples. 10. The measurement system of claim 3, wherein said means for converting the electrical signal into a sequence of digital samples comprises: (a) an amplifier having an input that is coupled to the detector and an output, said amplifier amplifying the electrical signal, producing an amplified electrical signal at its output; (b) an analog-to-digital converter that is coupled to the output of the amplifier converts the amplified electrical signal to the sequence of digital samples; and (c) a digital bandpass filter for rejecting a direct current bias and a high frequency noise component from the sequence of digital samples. 11. The measurement system of claim 3, wherein said means for processing the sequence of digital samples applies an amplitude windowing function to the sequence of numerical samples before applying the Fast Fourier Transform function. 12. The measurement system of claim 3, wherein said means for processing the sequence of digital samples comprises an oscilloscope. 13. The measurement system of claim 3, wherein said means for processing the sequence of digital samples comprises a programmed computer. 14. The measurement system of claim 3, wherein said means for processing the sequence of digital samples comprises an application specific integrated circuit. 15. The measurement system of claim 10, further comprising control means coupled to a gain control of the amplifier, for controlling a gain of the amplifier in response to a magnitude of the electrical signal level that is coupled to the input of the amplifier from the light sensitive detector. 16. The measurement system of claim 15, wherein the control means includes means for determining a signal-to-noise ratio of the electrical signal, said control means precluding a determining of the indication of the velocity from the signal produced by an object passing through the field of view when the signal-to-noise ratio is less than a predetermined minimum. 17. The measurement system of claim 15, wherein the control means is coupled to the means for processing and includes means for regulating a frequency range over which a mean frequency of the electrical signal from the detector is computed by the means for processing, in response to variations in a velocity of an object passing through the field of view. 18. The measurement system of claim 3, further comprising at least one light source for illuminating the field of view. 19. The measurement system of claim 18, wherein said at least one light source is disposed to provide an incident light that illuminates an object passing through the field of view. 20. The measurement system of claim 19, wherein said incident light stimulates an emission from an object passing through the field of view, and the light from an object passing through the field of view comprises a stimulated emission. 21. The measurement system of claim 19, wherein the incident light is at least partially absorbed by an object passing through the field of view, so that the light passing along the collection path comprises light that is not absorbed by that object. 22. The measurement system of claim 19, wherein the incident light is reflected from an object passing through the field of view toward the optical element. 23. The measurement system of claim 19, wherein the incident light stimulates an object passing through the field of view to fluoresce, so the light from an object passing through the field of view is emitted by that object. 24. The measurement system of claim 3, further comprising a source of a reference light field, wherein an intensity of the light from an object passing through the field of view is modulated by phase interference with the reference light field. 25. The measurement system of claim 3, wherein a flow of fluid in which objects are entrained passes through the field of view, such that the indication of the velocity of an object entrained in the fluid is determined by the means for processing. 26. The measurement system of claim 3, wherein a support on which a plurality of objects are disposed passes through the field of view, such that the indication of the velocity of an object on the support and a velocity of the support is determined by the means for processing. 27. The measurement system of claim 3, wherein said optical element comprises a lens. 28. The measurement system of claim 3, further comprising: (a) a first optical element disposed to direct light from an object along a first collection path; (b) a second optical element disposed in the first collection path to direct a portion of the light traveling along the first collection path, along a second collection path. 29. The measurement system of claim 28, wherein another light sensitive detector is employed to determine a characteristic of an object passing through the field of view other than the indication of the velocity of an object. 30. The measurement system of claim 3, wherein the collection path is directed through another field of view through which an object passes, further comprising: (a) another optical element disposed to direct light from an object passing through the other field of view along another collection path; and (b) at least one additional light sensitive detector disposed to receive the light traveling along the other collection path and employed to determine a characteristic of an object passing through the other field of view, said characteristic being other than an indication of the velocity of an object. 31. The measurement system of claim 3, further comprising means for sorting objects disposed downstream from said field of view. 32. The measurement system of claim 3, wherein the optical grating comprises an alternating sequence of opaque strips and transparent strips of substantially equal width. 33. The measurement system of claim 3, wherein said at least one light sensitive detector comprises a photosensitive diode. 34. The measurement system of claim 3, wherein said at least one light sensitive detector comprises a photomultiplier tube. 35. The measurement system of claim 3, further comprising a fluid supply in fluid communication with the field of view, said fluid supply providing a flow of fluid in which a plurality of objects are entrained, to the field of view. 36. The measurement system of claim 35, wherein each of the plurality of objects comprises at least one of a biological cell and a particulate component of a biological specimen. 37. The measurement system of claim 3, further comprising a solid support on which a plurality of objects are disposed, said solid support being moved through the field of view. 38. The measurement syste m of claim 37, further comprising a prime mover that moves said solid through the field of view. 39. An optical analysis system employed to determine an indication of a velocity of a relative movement between an object and the optical analysis system, and at least one additional characteristic of the object, comprising: (a) a first optical element disposed to direct light from an object along a first collection path; (b) a second optical element disposed in the first collection path to direct a portion of the light traveling from an object along the first collection path, along a second collection path; (c) an optical grating of substantially uniform pitch disposed in the second collection path, said optical grating modulating the light traveling along the second collection path, producing modulated light that has a modulation frequency proportional to a velocity of the relative movement between the object and the optical analysis system; (d) a light sensitive detector disposed in the second collection path to receive the modulated light, said light sensitive detector producing an electrical signal in response to the modulated light; (e) means coupled to the light sensitive detector to receive the electrical signal, for determining the indication of the velocity of the relative movement between the object and the optical analysis system as a function of the electrical signal using a Fast Fourier Transform (FFT ) function and producing a timing signal as a function of said velocity; and (f) a time delay integration (TDI) detector disposed to receive light traveling along the first collection path, said TDI detector being coupled to said means for determining the velocity, said TDI detector employing the timing signal to produce an output signal that is indicative of said at least one additional characteristic of the object. 40. The optical analysis system of claim 39, further comprising a control that is coupled to and controls the means for determining the indication of the velocity and the TDI detector. 41. An imaging system that determines an indication of a velocity of an object for use in determining at least one additional characteristic of an object, while there is relative movement between the object and the imaging system, comprising: (a) a collection lens disposed so that light traveling from an object passes through the collection lens and is directed along a first collection path; (b) a beam splitter that is disposed in the first collection path so that a portion of the light traveling from the object along the first collection path is diverted along a second collection path; (c) an optical grating of substantially uniform pitch disposed in the second collection path, said optical grating modulating the light traveling along the second collection path, to produce modulated light having a modulation frequency proportional to a relative velocity between the object and the imaging system; (d) a light sensitive detector disposed in the second collection path to receive the modulated light, said at least one light sensitive detector producing an electrical signal in response to the modulated light; (e) means coupled to the light sensitive detector, for determining the indication of the velocity of the relative movement between the object and the imaging system as a function of the electrical signal, using a Fast Fourier Transform function, said means producing a timing signal as a function of said velocity; (f) an imaging lens disposed in the first collection path, producing an image of the object; and (g) a time delay integration detector disposed in the first collection path to receive the image produced by the imaging lens, producing an output signal that is indicative of said at least one additional characteristic of the object, said time delay integration detector being coupled to the means for determining the indication of the velocity to receive the timing signal and producing the output signal