FIELD: optical engineering.
SUBSTANCE: method of producing light-diffracting microstructures in layer of photoresist material onto substrate is described. Microstructures are formed by means of application of first relief microstructure to at least one second structure which has to be diffraction structure for. Method consists of several stages. First, photoresist layer is made with first relief structure onto flat substrate, made by casting of relief array being opposite to substrate of relief array onto free surface of layer. Then relief array is removed. Then interference patter is formed onto relief structure. Coherent light is decomposed to partial beam and support beam. Partial beam and reference beam, which both form preliminary preset angle of crossing, induce interference onto cast first relief structure. Then interference pattern is formed, which pattern has high intensity bands separated by low intensity bands along azimuth in relation to first relief structure by means of rotation of substrate about normal line to surface of substrate. After that first relief structure is exposed in photoresistive layer by means of interference pattern during preset time. After that photoresist material is subject to development during preset time, moreover, material of photoresist, changed due to exposure, is partly removed and as a result, grooves of diffraction structure appear in first relief structure. Finally photoresist material is subject to drying. Development of photoresist is calculated in such a way that grooves of diffraction structure were of 500 nanometers as maximum. In the beginning, photoresistive layer is formed onto flat substrate, which layer is strengthened due to effect of heat. After that relief matrix, placed onto punch, is submerged into surface of photoresistive layer for form of first relief structure as negative print of relief array. As a result, replica-arrays with high degree of precision is made, which array can hardly be simulated.
EFFECT: reduced cost; high precision.
25 cl
