Method of manufacturing a microlens substrate, an opposed substrate for a liquid crystal panel, a liquid crystal panel and a projection type display apparatus

Abstract

A method of manufacturing a microlens substrate 10 is provided. The microlens substrate 10 is provided with a plurality of microlenses 8 . The method includes the steps of: preparing a substrate 101 with concave portions having two major surfaces, each of the plurality of concave portions 3 having a shape corresponding to that of each of the plurality of microlenses 8 being formed on one of the two major surfaces of the substrate 101 with concave portions; preparing a base material substrate 102′ mainly formed of a resin material, the base material substrate 102′ having two major surfaces; and pressure-joining the substrate 101 with concave portions to the base material substrate 102′ in a heating state. In this case, in the pressure-joining step, the substrate 101 with concave portions is joined to the base material substrate 102′ so that the plurality of concave portions 3 are filled with the resin material of the base material substrate 102′ which has been melted by the heat.

1 . A method of manufacturing a microlens substrate, the microlens substrate being provided with a plurality of microlenses, the method comprising the steps of: 
 preparing a substrate with concave portions having two major surfaces, each of the plurality of concave portions having a shape corresponding to that of each of the plurality of microlenses being formed on one of the two major surfaces of the substrate with concave portions;    preparing a base material substrate mainly formed of a resin material, the base material substrate having two major surfaces; and    pressure-joining the substrate with concave portions to the base material substrate in a heating state,    wherein in the pressure-joining step, the substrate with concave portions is joined to the base material substrate so that the plurality of concave portions are filled with the resin material of the base material substrate which has been melted by the heat.    
   
   
       2 . The method as claimed in  claim 1 , wherein the absolute value of the difference between an index of refraction of the constituent material of the substrate with concave portions and an index of refraction of the resin material is 0.10 or more.  
   
   
       3 . The method as claimed in  claim 1 , wherein the pressure-joining step is carried out under reduced pressure.  
   
   
       4 . The method as claimed in  claim 1 , further comprising the step of: 
 prior to the pressure-joining step, subjecting the one major surface of the substrate with concave portions on which the plurality of concave portions are formed to surface treatment for improving adhesion to the resin material.    
   
   
       5 . The method as claimed in  claim 1 , wherein, in the case where the thickness of the base material substrate prior to the pressure-joining step is defined as T 1  (mm) and the thickness from a flat portion of the substrate with concave portions at which the base material substrate is joined to the substrate with concave portions to one major surface of the base material substrate at which the base material substrate is not joined to the substrate with concave portions is defined as T 2  (mm), then T 1  and T 2  satisfy the relation: 0.5≦T 2 /T 1 ≦0.95.  
   
   
       6 . The method as claimed in  claim 1 , wherein the resin material is a thermoplastic resin material.  
   
   
       7 . The method as claimed in  claim 1 , wherein the pressure-joining step is carried out at a temperature higher than a glass transformation point of the resin material.  
   
   
       8 . The method as claimed in  claim 7 , wherein the glass transformation point of the resin material is 100° C. or higher.  
   
   
       9 . The method as claimed in  claim 1 , wherein the base material substrate is formed of a thermosetting resin material in a state where all monomers constituting the thermosetting resin material have not reacted so that the thermosetting resin material is not completely hardened.  
   
   
       10 . The method as claimed in  claim 9 , wherein the base material substrate contains a solvent for dissolving the monomers constituting the thermosetting resin material, and the amount of the solvent contained in the base material substrate is in the range of 1 to 30%.  
   
   
       11 . The method as claimed in  claim 10 , wherein in the pressure-joining step the solvent is removed.  
   
   
       12 . A microlens substrate manufactured using the method defined by  claim 1 .  
   
   
       13 . An opposed substrate for a liquid crystal panel comprising the microlens substrate defined by  claim 12 .  
   
   
       14 . A liquid crystal panel comprising the opposed substrate for a liquid crystal panel defined by  claim 13 .  
   
   
       15 . A liquid crystal panel, comprising: 
 a liquid crystal driving substrate provided with a large number of pixel electrodes;    the opposed substrate for a liquid crystal panel defined by  claim 13 , the opposed substrate for a liquid crystal panel being joined to the liquid crystal driving substrate so as to form a gap between the liquid crystal driving substrate and the opposed substrate for a liquid crystal panel; and    liquid crystal filled in the gap.    
   
   
       16 . The liquid crystal panel as claimed in  claim 15 , where in the liquid crystal driving substrate is a TFT substrate which includes the large number of pixel electrodes disposed in a matrix form, and a large number of thin film transistors respectively connected to the large number of pixel electrodes.  
   
   
       17 . A projection type display apparatus, comprising a plurality of light valves respectively provided with the liquid crystal panel defined by  claim 14 , wherein an image is projected using at least one of the plurality of light valves.