A variable aperture device suitable for photographing and filming of a camera module, comprising: a main body , wherein the main body has a light-transmitting region ; a fluid passage , wherein the fluid passage is provided in the light-transmitting region of the main body ; and a fluid accommodation cavity , wherein the fluid accommodation cavity is in communication with the fluid passage for a light-impermeable fluid being able to be driven to flow back and forth between the fluid accommodation cavity and the fluid passage to expand or reduce the light-transmitting area of the light-transmitting region , wherein the main body includes a base and a cover , and the main body forms a fluid groove and a cavity groove , and the cavity groove and the fluid groove communicate with each other, and the cover is provided on the main body and seals the fluid groove and the cavity groove to form the fluid passage and the fluid accommodation cavity , wherein the variable aperture device further comprises: a separator , wherein the separator is provided in the fluid accommodation cavity and for separating the fluid accommodation cavity into a fluid cavity and a gas cavity , and the fluid cavity is communicated with the fluid passage , and the fluid cavity is used to store the light-impermeable fluid , and the gas cavity is used to be sealed to store gas, and a driving unit , characterized in that the driving unit is configured to generate heat or absorb heat to directly or indirectly act on the gas in the gas cavity for transferring heat to or from the gas cavity . a main body , wherein the main body has a light-transmitting region ; a fluid passage , wherein the fluid passage is provided in the light-transmitting region of the main body ; and a fluid accommodation cavity , wherein the fluid accommodation cavity is in communication with the fluid passage for a light-impermeable fluid being able to be driven to flow back and forth between the fluid accommodation cavity and the fluid passage to expand or reduce the light-transmitting area of the light-transmitting region , wherein the main body includes a base and a cover , and the main body forms a fluid groove and a cavity groove , and the cavity groove and the fluid groove communicate with each other, and the cover is provided on the main body and seals the fluid groove and the cavity groove to form the fluid passage and the fluid accommodation cavity , wherein the variable aperture device further comprises: a separator , wherein the separator is provided in the fluid accommodation cavity and for separating the fluid accommodation cavity into a fluid cavity and a gas cavity , and the fluid cavity is communicated with the fluid passage , and the fluid cavity is used to store the light-impermeable fluid , and the gas cavity is used to be sealed to store gas, and a driving unit , characterized in that the driving unit is configured to generate heat or absorb heat to directly or indirectly act on the gas in the gas cavity for transferring heat to or from the gas cavity . a separator , wherein the separator is provided in the fluid accommodation cavity and for separating the fluid accommodation cavity into a fluid cavity and a gas cavity , and the fluid cavity is communicated with the fluid passage , and the fluid cavity is used to store the light-impermeable fluid , and the gas cavity is used to be sealed to store gas, and a driving unit , characterized in that the driving unit is configured to generate heat or absorb heat to directly or indirectly act on the gas in the gas cavity for transferring heat to or from the gas cavity . <EOS>