A few years ago, a microlithographic deposition process on infrared-transmitting substrates was developed in order to produce realistic infrared scenes for FLIR testing'. In recent months, the performance of this product, named Thermoscene, has been improved by improving the control over the production process. The two main results are:1. An increase of the number of simulated grey levels from 15 to 290, without reduction of the total number of pixels. 2. A decrease in imperfections, such as unwanted holes in the mesh deposition, to almost zero.The Thermoscene is useful as a component of infrared simulators2, to project realistic infrared scenes through collimating optics to a FLIR, missile seeker, etc., for testing purposes.