?. L-'intensité-Émise-dans-le-vert, ) -4 I15/2) par rapport à l'intensité émise dans le rouge (processus à 2 photons, transition 4 F9/2 -4 I15/2). C'est le rapport le plus souvent étudié du fait de la simplicité de sa détermination

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. Hamamatsu, R636-10 relié à un ordinateur 4. un filtre passe-bas 700LP (coupure à 700 nm) pour éliminer les raies parasites de la diode laser 5. un ensemble de lentilles permettant de focaliser le faisceau d'excitation sur l'échantillon (tache focale 2,5 mm × 0,25 mm)