Thermolase 1996 (unpublished)
Affiliated institution: Thermolase Corp, manufacturer of the first laser cleared in the US.
Cited in: Littler 1999
Two experiments described in Littler 1999 (p. 409) discussed unpublished 1996 in-house demonstrations of absorption as deep as 4 mm by Nd:YAG laser. In the first experiment, 2 mm layers of pig tissue were coated with a carbon solution similar to the kind used in the SoftLight device. The laser was able to vaporize carbon at 2 and 4 mm, but not at 6 mm. A second experiment showed that Nd:YAG penetrated with the best transmission rate, compared to other laser wavelengths. This was demonstarted by detecting amounts of energy that traveled through the earlobes and interdigital folds of subjects.
A third experiment sought to expand on the theory that lasers cause a shock wave which leads to mechanical damage of dividing cells in the hair matrix. Some have theorized that this shock wave is more important than heat in the process of laser hair removal. This effect was visually demonstrated in Littler 1999 (pp. 410-411) using carbon solution layered between glass slides. When irradiated with the Nd:YAG laser, the slides exploded from the resulting shock wave.