Significant differences exist between different temperature sensors or temperature measurement device types. Using one perspective, how they work, they can be simply divided into two groups, contact and noncontact.
The links below take you to descriptive pages on each type with a breakdown by more specific, detailed types under that first, simple classification.
There are also vendors of each sensor type, some vendors sell more than one type and some sell nearly all types, but not always all brands.
There are differences between brands and the differences are most evident among those device types for which there are few if any recognized standards.
Start your search either for a specific temperature measurement device type or go to the vendor page index and you can access the vendors of specific types from there.
Both contact and non-contact sensors require some assumptions and inferences in use to measure temperature. Many, many well-known uses of these sensors are very straightforward and few, if any, assumptions are required. So, it is easier to seek a solution or application that someone else has already pioneered of you.
Other uses require some careful analysis to determine the controlling aspects of influencing factors that can make the apparent temperature quite different from the indicated temperature.
Remember the truism that: all sensor have errors in their readings – all the time. A key secret to high quality measurement results is to have confidence in the error estimates and a high confidence that likely errors are acceptable in your case
Neglecting to make a careful error analysis can result in error much larger than the assumed values.
It is worth noting that all competent error analyses start with the uncertainties assigned to the traceable calibration of the sensor itself. Without traceable calibration, one is forced to make assumptions.
(You know what the word ass|u|me means, we hope.)