help me to find the component details

If there is a component ID on the board, it could help narrow it down a bit. Like "Qx" is for transistors and "Ux" for an integrated circuit, etc.
Keep in mind the TO92 is a very popular package that has been around since the 60's and used for many types of devices such as bipolar transistors, FETs SCRs, Triacs, Voltage regulator ICs, current sources and more, so your question is not an easy one.
As Mooly suggested, the more info the better.