Backlight module and method for manufacturing the same, and display device

A method for manufacturing a backlight module comprising:

• a substrate;
• a plurality of LED chips arranged on a side of the substrate and electrically connected to the substrate;
• and
• a first film disposed on a side of each of the plurality of LED chips facing away from the substrate, wherein each of the first films are formed in one piece,
• wherein an orthographic projection of the at least one LED chip on a plane of the substrate is located within an orthographic projection of the first film on the plane of the substrate,
• the first film has a plurality of channels penetrating through the first film,
• each of the plurality of channels comprises a first side close to the at least one LED chip and a second side facing away from the at least one LED chip,
• each of the plurality of channels is filled with a channel filling portion having a first end surface located on the first side and a second end surface located on the second side,
• the first film has a refractive index nl, and the channel filling portion has a refractive index n2, where n2>n1, wherein total reflection occurs when light emitted from the LED chips is transmitted in the channels, and
• the first film has a first region and a second region surrounding the first region, an orthographic projection of the first region on the plane of the substrate at least partially overlaps with an orthographic projection of the at least one LED chip of on the plane of the substrate;
• in the first region, an area of the first end surface of the channel filling portion is smaller than an area of the second end surface of the channel filling portion in a same channel;
• and in the second region, an area of the first end surface of the channel filling portion is larger than an area of the second end surface of the channel filling portion in a same channel,
• wherein the method comprises:
• preparing the substrate and a finished film layer, wherein the plurality of LED chips is electrically connected to a surface of the substrate;
• and
• arranging the finished film layer on a side of the plurality of LED chips facing away from the substrate in such manner that the finished film layer covers at least one LED chip of the plurality of LED chips,
• wherein the finished film layer comprises a first film and a channel filling portion.

A display device, comprising:

• a display panel;
• and
• a backlight module configured to provide backlight to the display panel, wherein the backlight module comprises:
• a substrate;
• a plurality of LED chips arranged on a side of the substrate and electrically connected to the substrate;
• and
• a first film disposed on a side of each of the plurality of LED chips facing away from the substrate, wherein each of the first films are formed in one piece,
• wherein an orthographic projection of the at least one LED chip on a plane of the substrate is located within an orthographic projection of the first film on the plane of the substrate,
• the first film has a plurality of channels penetrating through the first film,
• each of the plurality of channels comprises a first side close to the at least one LED chip and a second side facing away from the at least one LED chip,
• each of the plurality of channels is filled with a channel filling portion having a first end surface located on the first side and a second end surface located on the second side,
• the first film has a refractive index nl, and the channel filling portion has a refractive index n2, where n2>n1, wherein total reflection occurs when light emitted from the LED chips is transmitted in the channels, and
• the first film has a first region and a second region surrounding the first region, an orthographic projection of the first region on the plane of the substrate at least partially overlaps with an orthographic projection of the at least one LED chip of on the plane of the substrate;
• in the first region, an area of the first end surface of the channel filling portion is smaller than an area of the second end surface of the channel filling portion in a same channel;
• and in the second region, an area of the first end surface of the channel filling portion is larger than an area of the second end surface of the channel filling portion in a same channel.