Sequential beam splitting in a radiation sensing apparatus

An apparatus comprising:

• a light source;
• a first surface configured to split light rays from the light source to reflect first light rays and transmit second light rays;
• one or more second surfaces each configured to split at least a portion of the second light rays transmitted from the first surface to reflect third light rays;
• light-reflecting surfaces configured in a plane that is oblique to the first and second surfaces, wherein:
• each light-reflecting surface moves independently of the other light-reflecting surfaces and in response to an intensity of infrared radiation at a respective location of the light-reflecting surface;
• and
• the first and third light rays are reflected by the light-reflecting surfaces towards an imaging surface;
• and
• a signal processing unit configured to determine displacements of light rays, including the first and third light rays, on the imaging surface to generate an image that indicates the radiation intensity at each of the locations.

A method comprising:

• splitting, by a first surface, light rays from a light source to reflect first light rays and transmit second light rays;
• splitting, by a second surface, at least a portion of the second light rays transmitted from the first surface to reflect third light rays;
• reflecting the first and third light rays by light-reflecting surfaces towards an imaging surface, wherein each light-reflecting surface moves independently of the other light-reflecting surfaces and in response to an intensity of infrared radiation at a respective location of the light-reflecting surface;
• and
• determining displacements of light rays, including the first and third light rays, on the imaging surface to generate an image that indicates the radiation intensity at each of the locations.