What does 'geometric efficiency' refer to in the context of gamma cameras?

Geometric efficiency in gamma cameras relates directly to the ability of the camera to detect radiation emitted from a point source. This concept encompasses how well the camera can capture the radiation that is emitted in various directions from the source, which is crucial for producing accurate images.

In this context, geometric efficiency is affected by factors such as the design of the camera, the type of detector used, and the distance from the source to the camera. A higher geometric efficiency means that the camera can detect a larger percentage of the emitted radiation, leading to better sensitivity and image quality. This is essential for ensuring accurate diagnostic information in medical imaging.

Other options, while they may relate to camera performance, do not capture the specific definition of geometric efficiency in the same way. The overall resolution of images, while important, is more about clarity and detail than the ability to detect radiation. The speed of processing images concerns how quickly data is converted into a usable format rather than the efficiency of radiation detection. Cost efficiency does not have a direct impact on the fundamental function of detecting radiation and is more about the economic aspects of operating the camera.