Electro-optics manufacturer Photonis USA said it has received a patent to produce resistive glass tubes with nonlinear gradient electrical resistance changes, a process that can be used to fabricate solid-piece reflectron lenses for reflectron-type time-of-flight (TOF) mass spectrometers (MS). Reflectron lenses in TOF-MS create an electrostatic field to alter ion flow, providing a longer flight path and greater resolution. Current reflectron-type TOF-MS instruments use complex multipiece stacked ring assemblies, which require time-consuming assembly and cleaning processes. They also need a voltage divider in each layer to reverse ion direction. A reflectron lens made with resistive glass, however, provides a solid assembly replacement for stacked ring assemblies while also offering the same ability to alter ion flow. The glass piece is also simpler to replace and clean. The resistive glass consists of an alkali-doped lead silicate that has been reduced to make the surface a semiconductor. A previously awarded patent encompassed a uniform electric field; the latest patent documents that manufacturing varied, nonlinear electric fields is also possible. For more information, visit: www.photonis.com