Abstract: A positron microscope utilizes a time-of-flight adjustment and a beam gate to distinguish images produced by respective types of positronium events. If the time-of-flight of secondary electrons is approximately between 30 and 40 ns, then the electron image will represent prompt annihilations and parapositronium distributions in the target. For time-of-flight between 50 and 100 ns longer than the processing time of the electronic gating circuitry, the electron image will be a map of long-lived orthopositronium events.

Abstract: A positron microscope system utilizing image enhancement to overcome problems associated with low positron source flux can be operated in transmission and reflection modes. In the practice of the invention, slow positrons which are emitted after moderation of a positron source are focused, as a source beam, on a specimen target. In some embodiments, the source beam is swept over the specimen target, to effect scanning thereof. Image enhancement is effected by a channel electron multiplier array (CEMA) which may have a plurality of plates. The cloud of electrons which is generated by the CEMA in response to each incident positron is accelerated toward a long persistence phosphor screen. Image acquisition is achieved by a low light video system which delivers its signal to a memory which stores the data. The data is subsequently subjected to an image analysis algorithm which facilitates accumulation and signal averaging.

Abstract: A positron microscope system utilizing image enhancement to overcome problems associated with low positron source flux can be operated in transmission and reflection modes. In the practice of the invention, slow positrons which are emitted after moderation of a positron source are focused, as a source beam, on a specimen target. In some embodiments, the source beam is swept over the specimen target, to effect scanning thereof. Image enchancement is effected by a channel electron multiplier array (CEMA) which may have a plurality of plates. The cloud of electrons which is generated by a CEMA in response to each incident positron is accelerated toward a long persistence phosphor screen. Image acquisition is achieved by a low light video system which delivers its signal to a memory which stores the data. The data is subsequently subjected to an image analysis algorithm which facilitates accumulation and signal averaging.