Light source module, backlight module and display device

A light source module, comprising a light emitting element and a light adjusting element, the light adjusting element comprises a first substrate and a second substrate opposite to each other, an accommodation chamber is formed between the first substrate and the second substrate, a fluid layer is filled in the accommodation chamber, the fluid layer comprises polar fluid and non-polar fluid which are immiscible,

• the first substrate comprises a light guide layer, a first electrode layer and a dielectric layer, the light emitting element is provided at a side of the light guide layer, the first electrode layer is provide on a light exiting surface side of the light guide layer, the dielectric layer is provided on a side of the first electrode layer away from the light guide layer, the dielectric layer is in contact with the fluid layer, a refractivity of the dielectric layer is equal to a refractivity of the light guide layer, a refractivity of the polar fluid is greater than or equal to the refractivity of the dielectric layer, a refractivity of the non-polar fluid is less than the refractivity of the dielectric layer,
• the light adjusting element is divided into a plurality of control regions, the first electrode layer comprises a plurality of first electrodes corresponding to the control regions one to one, a second electrode layer is provided in the first substrate or the second substrate,
• a control electric field is formed between the first electrode and the second electrode layer to control hydrophilicity and hydrophobicity of the polar fluid, in the control region corresponding to the first electrode, on a surface of the dielectric layer.