Detection method for display panel, display panel and display device

A detection method for a display panel, wherein the display panel has a display area and a non-display area,

• wherein the display panel comprises:
• a plurality of data lines arranged in the display area, wherein one of the plurality of data lines is connected to at least one sub-pixel in one pixel column;
• and
• at least one signal line, at least one switch unit, and at least one switch control line that are arranged in the non-display area, wherein one signal line of the at least one signal line is electrically connected to at least one data line through one switch unit of the at least one switch unit, and the switch unit comprises a control terminal electrically connected to one of the at least one switch control line, an input terminal electrically connected to the signal line, and an output terminal electrically connected to the at least one data line;
• and
• wherein the detection method comprises:
• providing a pulse signal to the signal line;
• controlling the switch unit to be turned on once in a period of at least one signal hopping of the pulse signal on the signal line, to electrically connect the signal line with the at least one data line, and writing a data signal to the at least one data line through the signal line, wherein the data signal is the pulse signal truncated in the period of the at least one signal hopping of the pulse signal;
• and
• controlling, based on the data signal, at least one sub-pixel connected to the at least one data line to emit light;
• and determining that the signal line has a micro-crack when a brightness of the at least one sub-pixel connected to the at least one data line corresponding to the signal line is different from a reference brightness.