An electro-optical physiologic sensor comprises a printed circuit board (PCB) and a light emitter and a photodetector respectively mounted to the PCB. A first sensor element is disposed on the PCB and comprises a first electrode configured to contact tissue of a subject and a first light channel co-located with the first electrode, the first light channel optically coupled to the light emitter and configured to direct light into the subject's tissue. A second sensor element is disposed on the PCB and comprises a second electrode configured to contact the subject's tissue and a second light channel co-located with the second electrode, the second light channel optically coupled to the photodetector and configured to receive light from the tissue of the subject resulting from the light generated by the light emitter.

Provided is a gas sensor that can suppress characteristic variation caused by deformation of a semiconductor substrate. The gas sensor (1) includes a substrate (redistribution layer 30), a light-emitting element (11) provided at a front surface (30a) or embedded in the substrate, a light-receiving element (12) that is provided at the front surface or embedded in the substrate and that receives light emitted from the light-emitting element, and a plurality of external connection terminals (40) at a rear surface (30b) that is an opposite surface to the front surface of the substrate. At least a portion of the plurality of external connection terminals is electrically connected to the light-emitting element and the light-receiving element. The plurality of external connection terminals is arranged such that, in plan view, the light-emitting element and the light-receiving element are not present on a line linking any two external connection terminals.

Provided is a gas sensor that can suppress characteristic variation caused by deformation of a semiconductor substrate. The gas sensor (1) includes a substrate (redistribution layer 30), a light-emitting element (11) provided at a front surface (30a) or embedded in the substrate, a light-receiving element (12) that is provided at the front surface or embedded in the substrate and that receives light emitted from the light-emitting element, and a plurality of external connection terminals (40) at a rear surface (30b) that is an opposite surface to the front surface of the substrate. At least a portion of the plurality of external connection terminals is electrically connected to the light-emitting element and the light-receiving element. The plurality of external connection terminals is arranged such that, in plan view, the light-emitting element and the light-receiving element are not present on a line linking any two external connection terminals.

A semiconductor package may include: a pair of first input terminals arranged adjacent to each other, which is connected to a terminal pair of a first light-receiving element which outputs a first current signal as a function of a light reception amount of light emitted from a light source; a pair of second input terminals arranged adjacent to each other, which is connected to a terminal pair of a second light-receiving element which outputs a second current signal as a function of the light reception amount of light emitted from the light source; a third terminal arranged adjacent to one in the pair of first input terminals and to one in the pair of second input terminals; and a generation unit which generates a digital signal based on the first current signal and the second current signal.

A semiconductor package may include: a pair of first input terminals arranged adjacent to each other, which is connected to a terminal pair of a first light-receiving element which outputs a first current signal as a function of a light reception amount of light emitted from a light source; a pair of second input terminals arranged adjacent to each other, which is connected to a terminal pair of a second light-receiving element which outputs a second current signal as a function of the light reception amount of light emitted from the light source; a third terminal arranged adjacent to one in the pair of first input terminals and to one in the pair of second input terminals; and a generation unit which generates a digital signal based on the first current signal and the second current signal.