Spatial characteristics of a thermal lens induced by a Gaussian beam in an absorbing liquid are studied using a nonlinear geometrical optics approximation. We show that the thermal lens in the vicinity of the sample cell is a focal point of light and a ring-of-light foci located in a plane displaced with respect to the focal point. The distance between the focal point and the ring-of-light foci decreases when the light power is increased. Experiments performed on an ethanol solution of iodine confirm the existence of this microscopic structure. The distance between the focal point and the ring of foci was measured for samples of different absorption coefficients. A good agreement between theory and experiment was obtained.