Thermal Lens Spectrophotometry

Thermal Lens Spectroscopy

Confocal thermal-lens microscope.

The use of a confocal detection scheme in a dual-beam thermal-lens microscope is presented. The scheme allows the measurement of absorption factors down to 1.2 x 10(-7) in a 0.35-microm3 volume by use of a heating laser power of 100 mW incident upon the sample. Results are presented that prove that a 450-nm axial resolution is possible when a 1.2 water immersion objective lens with a N.A. of 1....

Unusual behavior of thermal lens in alcohols.

We use a femtosecond pump-probe Z-scan technique to measure the thermal lens (TL) signal in a homologous series of primary alcohols. The trend in these experimentally measured TL signals deviates in a counterintuitive manner from the ones calculated using theoretical models that are only based on the macroscopic parameters. Introspection shows that the present TL theories are based on heat cond...

The Neutron Silicon Lens : An update of the thermal neutron lens results

This paper introduces the concept of the Neutron Silicon Lens (NSL) and provides and update on the experimental results achieved to date. The NSL design is a cylindrical neutron lens based on the use of multiple neutron mirrors supported and separated by silicon wafers. Such lenses would have many applications in both the primary and scattered beams on neutron instruments, and would lead to imm...

Contributions of transient absorption and population lens in thermal lens spectroscopy

Contaminations of the population lens and transient absorption in thc obsened thermal lens signal sometimes cause a misinterpretation of the signal. Rcccntly, we ha1.c developed several methods to evaluate the relative contributions of these components in thc observed thermal lens signal. These methods with reccnt results are sumtnarizcd, and mcrits and limitations of each method are discussed.