在拉曼测量中采用超高速门控电荷耦合器件相机来有效抑制荧光信号
A high level of fluorescence background signal rejection was achieved for solid and powder samplesby using a combination of simple low-resolution spectrograph and ultrafast gated charge coupleddevice ~CCD! camera. The unique timing characteristics of the CCD camera match exceptionallywell to characteristics of a Ti:sapphire oscillator allowing fast gated light detection at a repetitionrate of up to 110 MHz, making this approach superior in terms of the duty cycle in comparison withother time-resolved Raman techniques. The achieved temporal resolution was about 150 ps under785 nm Ti: sapphire laser excitation. At an average excitation power up to 300 mW there was nonoticeable sample damage observed. Hence, the demonstrated approach extends the capabilities ofRaman spectroscopy regarding the investigation of samples with a short fluorescence lifetime. Thecombination of a spectrometer and a gated CCD camera allows simultaneous study of spectral andtemporal characteristics of emitted light. This capability opens an exciting possibility to build auniversal instrument for solving multitask problems in applied laser spectroscopy