Spectral wavelength discrimination system and method for using

A system for determining the wavelength of radiation emitted from a predetermined spatial region of a sample, said system comprising:

• means for irradiating a sample region to produce emitted radiation;
• an optically opaque housing positioned for receiving said emitted radiation;
• band-pass filter means for transmitting a predefined wavelength range of interest;
• optical means for optically re-imaging a region of said sample to a predetermined re-imaging plane;
• first aperture means for limiting the angle of acceptance of said optical means for re-imaging;
• second aperture means for collecting portions of said emitted radiation by blocking any of said emitted radiation arriving from areas outside of a predetermined spatial region of said sample;
• linear wavelength filter means for selectively directing predetermined fractions of said beam of radiation at each wavelength within a wavelength range of at least about 300 nm by either reflectance or transmission into two output beams over a predefined wavelength range,
• said predetermined fractions increasing in one of said output beams and decreasing in the other of said output beams with increasing wavelength, wherein the radiation loss from said selectively directing means is small and relatively insensitive to wavelength;
• means for measuring the total amount of radiation in each of said output beams;
• and
• means for determining the wavelength of said emitted beam from said two measured amounts of radiation:
• said band-pass filter means, said first aperture means, said optical means for re-imaging, said second aperture means, and said means for selectively directing predetermined fractions, being aligned along a common optical path and located within said optically opaque housing.

A system for determining the wavelengths of radiations emitted from each of a plurality of sample regions, said system comprising:

• means for irradiating each of said plurality of sample regions to produce emitted radiation from each said sample region;
• an optically opaque multiple channel housing for receiving said emitted radiation from a plurality of small areas;
• a plurality of separate analysis channels, each said channel configured for evaluating radiation emitted from a different sample region, each said channel being substantially optically isolated from each said other channel;
• each said analysis channel comprising:
• band-pass filter means for transmitting a predefined wavelength range of interest;
• optical means for optically re-imaging a region of said sample to a predetermined re-imaging plane;
• first aperture means for limiting the angle of acceptance of said optical means for re-imaging;
• second aperture means for collecting portions of said emitted radiation by blocking any of said emitted radiation arriving from areas outside of a predetermined spatial region of said sample;
• means for selectively directing predetermined fractions of said collected portion of said emitted radiation at each wavelength respectively into two output beams over a predefined wavelength range of at least 300 nm,
• said predetermined fractions increasing in one of said output beams and decreasing in the other of said output beams with increasing wavelength, wherein the radiation loss from said selectively directing means is small and relatively insensitive to wavelength;
• means for measuring an amount of radiation in each of said output beams;
• and
• means for determining the wavelength of said collected portion of said beam of emitted radiation from said two measured amounts of radiation;
• said band-pass filter means, said first aperture means, said optical means for re-imaging, said second aperture means, and said means for directing, being aligned along a common optical path and located within said optically opaque housing.

A method of determining the wavelength of a beam of emitted radiation from a small area, comprising the steps of:

• forming a beam of radiation from radiation coming from said small area;
• selectively directing predetermined fractions of said beam of radiation at each wavelength into two output beams over a predefined wavelength range of at least 300 nm,
• said predetermined fractions increasing in one of said output beams and decreasing in the other of said output beams with increasing wavelength, wherein the radiation loss from said selectively directing means is small and relatively insensitive to wavelength,
• measuring the total amount of radiation in each of said first and second output beams;
• and
• determining the wavelength of said emitted beam from said two measured amounts of radiation.

A method for scanning a gel in a gel electrophoresis to detect fluorescent bands, said method comprising:

• in a first series of determinations:
• forming a plurality of beams of radiation from radiation coming from a plurality of small areas in a line orthogonal to the direction of movement of ions in said gel;
• selectively directing predetermined fractions of each of said beams of radiation at each wavelength into two output beams over a predefined wavelength range of at least 300 nm,
• said predetermined fractions increasing in one of said output beams and decreasing in the other of said output beams with increasing wavelength, wherein the radiation loss from said selectively directing means is small and relatively insensitive to wavelength,
• measuring the total amount of radiation in each of said first and second output beams from each of said small areas;
• determining the wavelength of each of said emitted beams from said two measured amounts of radiation for each of said small areas;
• and
• repeating said first series of determinations from a plurality of small areas adjacent to said plurality of small areas measured in said first series, until substantially all of said gel has been scanned.