Method for forming a diffusive-type light reflector

A method for fabricating diffusive-type light reflector, said diffusive-type light reflector being used for scattering incident light into a predetermined angular area away from specular ray, said method comprising:

• forming a photoresist layer on a substrate;
• using an exposing step to expose said photoresist layer;
• exposing said photoresist layer under defocus exposure through a slit-width-adjusting mask, said slit-width-adjusting mask comprising a plurality sets of slit, each set of slit comprising several portions having width p2, each portion comprising a slit, a first portion under light source of said defocus exposure having a first exposure p1, a second portion under light source of said defocus exposure having a second exposure q1, transparent area within said second portion having width of q2, said first exposure p1 being greater than said second exposure q1, and (q2)/(p2)=(q1)/(p1);
• baking said photoresist layer;
• developing said photoresist layer to form a photoresist pattern, said photoresist pattern comprising a plurality of pumps, each of said plurality of pumps comprising a first flat portion and a second flat portion, altitude of said first flat portion being higher than altitude of said second flat portion, said first flat portion being adjacent to said second flat portion;
• and
• baking said developed photoresist pattern, edges of each of said plurality of pumps of said photoresist pattern being smoothed, each of said plurality of baked pumps comprising a first surface and a second surface, said first surface being longer than said second surface, a first angle between said first surface and said substrate being unequal to a second angle between said second surface and said substrate, said plurality of pumps being randomly distributed on said substrate;
• and
• forming a reflective layer on said photoresist pattern, a normal direction of said first surface being pointing to a predetermined direction enabling reflective light of said incident light reflected by said reflective layer scattered into said predetermined angular area.

A method for fabricating diffusive-type light reflector, said diffusive-type light reflector being used for scattering incident light into a predetermined angular area away from specular ray, said method comprising:

• forming a photoresist layer on a substrate;
• exposing said photoresist layer under defocus exposure through a slit-width-adjusting mask, said slit-width-adjusting mask comprising a plurality sets of slit, each set of slit comprising several portions having v blocks, a first portion comprising v transparent blocks, a second portion comprising k oblique blocks, said first portion under light source of said defocus exposure having a first exposure p1, said second portion under light source of said defocus exposure having a second exposure q1, said first exposure p1 being greater than said second exposure q1, and (v-k)/(v)=(q1)/(p1);
• baking said photoresist layer;
• developing said photoresist layer to form a photoresist pattern, said photoresist pattern comprising a plurality of bumps, each of said plurality of bumps comprising a first surface and a second surface, said first surface having a longer slant than said second surface, a first angle φ between said first surface and said substrate being unequal to a second angle θ between said second surface and said substrate;
• and
• forming a reflective layer on said photoresist pattern, a normal direction of said first surface being pointing to a predetermined direction enabling reflective light of said incident light reflected by said reflective layer scattered into said predetermined angular area.