Controlling pulses in optical microscopy

A method for imaging a sample, comprising:

• providing at least one input optical wave that includes pulses that are approximately uniformly spaced by a time delay;
• directing the input optical wave to focus on a first portion of the sample;
• detecting energy from an output optical wave generated from a nonlinear optical interaction in the first portion of the sample with the optical wave during a first time period that is about equal to or longer than the time delay;
• temporarily preventing the input optical wave from reaching the sample during a second time period that is long enough for most of an amount of heat built up in the sample by the input optical wave during the first time period to be dissipated;
• and
• generating a representation of the first portion of the sample based on the detected energy from the output optical wave.

A system for imaging a sample characterized by a limit on incident optical energy absorbed over a given time period, comprising:

• a source of at least one input optical wave that includes pulses that each have a full-width half-maximum time duration of more than 100 picoseconds and a pulse energy sufficiently large such that a sufficient number of consecutive pulses absorbed by the sample would exceed the limit;
• a microscope configured to direct the input optical wave to focus on a first portion of the sample;
• and
• a detection sub-system configured to
• detect energy from an output optical wave generated from a nonlinear optical interaction in the first portion of the sample with the input optical wave, and
• generate a representation of the first portion of the sample based on the detected energy from the output optical wave.