Photometric device

• US 5,557,398 A
• Filed: 04/15/1994
• Issued: 09/17/1996
• Est. Priority Date: 04/15/1994
• Status: Expired due to Term

• Current Assignee: Molecular Devices
• Original Assignee: Molecular Devices
• Inventors: Wechsler, Mark, Hafeman, Dean G., Chow, Calvin Y., Lacy, Michael M., Ogle, David G., Barney, Howard H., Kaye, Roger A., Crawford, Kimberly L.
• Primary Examiner(s): Hantis, K.
• Application Number:
  US08/228,436
• Time in Patent Office: 886 Days
• Field of Search: 356/318-319, 356/325, 356/410, 356/328, 356/440, 356/436, 356/246, 356/427, 250/227.23
• US Class Current: 356/318
• CPC Class Codes: G01N 21/253 for batch operation, i.e. multisample apparatus analytical automats G01N35/00
• CPC Class Codes: G01N 21/31 Investigating relative effect of material at wavelengths characteristic of specific elements or molecules, e.g. atomic absorption spectrometry G01N21/72 takes precedence
• CPC Class Codes: G01N 21/33 using ultraviolet light G01N21/39 takes precedence
• CPC Class Codes: G01N 2201/0231 Thermostating
• CPC Class Codes: G01N 2201/0446 Multicell plate, sequential
• CPC Class Codes: G01N 2201/1222 Endpoint determination; reaction time determination
• CPC Class Codes: G01N 2201/127 Calibration; base line adjustment; drift compensation
• CPC Class Codes: G01N 35/028 having reaction cells in the form of microtitration plates

Abstract

The present invention relates to a photometric device for measuring optical parameters. The invention functions in the ultraviolet light range through use of a monochromator and splits the test light in multiple channels by a rotor assembly, including a mirror.

Claims

1. A photometric device for measuring an optical property of a plurality of samples, contained within a plurality of vessels in multi-assay plate, comprising, in combination;

an excitation light source that emits a first light having a first wavelength range on the order of 200 to 1100 nanometers,

a monochromator, responsive to said first light received from said excitation light source, for producing a second light having a predetermined second wavelength range on the order of 250 to 750 nanometers;

an optical fiber, coupled to said monochromator and extending in a first direction therefrom, for receiving said second light and transmitting a test light substantially in said first direction;

a distribution network including a series of distribution optical fibers extending in a second direction;

rotor means for receiving said test light from said optical fiber and for redirecting said test light substantially in said second direction and sequentially into each of said distribution optical fibers;

said rotor means including at least a first mirror operable in a series of mirror positions in correspondence with said series of distribution optical fibers, respectively;

said distribution network transmitting said test light substantially vertically and sequentially through said vessels, said test light being affected by each of said samples to produce a plurality of measurement light flashes;

and photodetector means for receiving said measuring light flashes and responsively providing a plurality of electrical measurement output signals representative of said optical property for each of said optical property for each of said samples, respectively.

2. A photometric device as claimed in claim 1 wherein said rotor means includes a second mirror and a lens interposed said first mirror and said second mirror.

3. A photometric device as claimed in claim 2 wherein said first and second mirrors and said lens are mechanically linked and move in unison.

4. A photometric measurement device as claimed in claim 3 further comprising:

plate carrier means for intermittently advancing and vibrating said multi-assay plate; and

microprocessor means, coupled to said rotor means, to said monochromator, to said photodetector means and to said plate carrier means, for controllably activating said plate carrier means, controllably sequencing said rotor means through said mirror positions, selecting said second predetermined wavelength range, and analyzing said electrical measurement output signals.

5. A photometric device as claimed in claim 4 further comprising temperature control means, substantially enclosing said multi-assay plate in a closed state, for regulating the temperature of said samples during measurement, said temperature control means including supply means for generating a stream of heated air and a baffle, interposed said multi-assay plate and said supply means, for distributing said heated air in a predetermined pattern upon said multi-assay plate.

6. A photometric device as claimed in claim 5 wherein said supply means includes a heater and a fan for moving ambient air over said heater to provide said stream of heated air and wherein said baffle includes central apertures and peripheral apertures, said central apertures being larger than said peripheral apertures.

7. A photometric measurement device as claimed in claim 6 further comprising:

plate carrier means for intermittently advancing and vibrating said multi-assay plate; and

microprocessor means, coupled to said rotor means, to said monochromator, to said photodetector means and to said plate carrier means, for controllably activating said plate carrier means, controllably sequencing said rotor means through said mirror positions, selecting said second predetermined wavelength range, and analyzing said electrical measurement output signals.

8. A photometric device as claimed in claim 1 wherein said excitation light source includes a flash lamp providing a series of first light flashes, said test light including a series of test light flashes corresponding thereto.

9. A photometric device as claimed in claim 8 further comprising beam splitter means for diverting a portion of each of said test light flashes to provide a corresponding series of reference light flashes and for delivering said reference light flashes to said photodetector means.

10. A photometric device as claimed in claim 9 wherein said beam splitter means interposes said optical fiber and said rotor means.

11. A photometric device as claimed in claim 10 further comprising:

temperature control means, substantially enclosing said multi-assay plate in a closed state, for regulating the temperature of said samples during measurement, said temperature control means including supply means for generating a stream of heated air and a baffle, interposed said multi-assay plate and said supply means, said baffle having central apertures and peripheral apertures directing said heated air against said multi-assay plate and about said vessels; and

microprocessor means, coupled to said excitation light source, to said rotor means, to said photodetector means and to said temperature control means, for controllably activating said flash lamp, controllably sequencing said rotor means through said mirror positions, analyzing said output signals in accordance with said reference light flashes, respectively, and controllably activating said supply means.

12. A photometric device as claimed in claim 1 wherein said first wavelength range is a continuum and said monochromator includes a diffraction grating and slit means for providing said second wavelength range for receipt by said optical fiber.

13. A photometric device as claimed in claim 12 wherein said excitation light source includes a flash lamp providing a series of first light flashes, said test light including a series of test light flashes corresponding thereto, said photodetector means including a reference photodetector.

14. A photometric device as claimed in claim 13 further comprising splitter means for diverting a portion of each of said test light flashes to said reference photodetector as a series of electrical reference signals.

15. A photometric measurement device as claimed in claim 14 further comprising:

plate carrier means for intermittently advancing and vibrating said assay plate; and

microprocessor means, coupled to said rotor means, said monochromator, said photodetector means and said plate carrier means, for controllably activating said plate carrier means, controllably sequencing said rotor means through said mirror positions, setting said second wavelength range, and analyzing said electrical measurement output signals in accordance with said electrical reference signals.

16. In a photometric device of the type utilizing a multi-assay plate and an optical fiber for transmitting light from a source in a first direction, the improvement comprising, in combination:

a series of distribution optical fibers extending in a second direction; and

rotor means, including at least a first mirror having a series of operational positions, for receiving said light from said optical fiber and for redirecting said light sequentially along each of said distribution optical fibers, said operational positions being in correspondence with said distribution optical fibers, respectively, second mirror in fixed relationship to said first mirror and a lens interposed and in a fixed relationship to said first and second mirrors.