Near-infrared absorbing glass and near-infrared cut filter

Abstract

The near-infrared absorbing glass, which contains at least four kinds of main cations selected from the group consisting of P ions, Li ions, Cu ions, Al ions, Ba ions, Sr ions, Ca ions, Mg ions, Zn ions, K ions, Na ions, La ions, Gd ions, and Y ions, contains P ions, Li ions, and Cu ions as essential cations, and contains at least O ions as anions, wherein a ratio (O ion/P ion) of a content of O ions relative to a content of P ions is 3.15 or less; in a glass composition indicated by anion %, a content of O ions is 90.0 anion % or more; and in an oxide-based glass composition on a molar basis, a total content of oxides of the main cations is 90.0% or more, and a total content (MgO+Al 2 O 3 ) of MgO and Al 2 O 3 is 8.0% or less.

1 . A near-infrared absorbing glass,
 which comprises at least four kinds of main cations selected from the group consisting of P ions, Li ions, Cu ions, Al ions, Ba ions, Sr ions, Ca ions, Mg ions, Zn ions, K ions, Na ions, La ions, Gd ions, and Y ions,   comprises P ions, Li ions, and Cu ions as essential cations,   and comprises at least O ions as anions,   wherein   a ratio of a content of O ions relative to a content of P ions (O ion/P ion) is 3.15 or less;   in a glass composition indicated by anion %, a content of O ions is 90.0 anion % or more; and   in an oxide-based glass composition on a molar basis,   a total content of oxides of the main cations is 90.0% or more,   a total content of MgO and Al 2 O 3 (MgO+Al 2 O 3 ) is 8.0% or less,   a ratio of a total content of Na 2 O, K 2 O, and ZnO relative to a content of Li 2 O ((Na 2 O+K 2 O+ZnO)/Li 2 O) is 2.4 or less,   a total content of B 2 O 3  and SiO 2  (B 2 O 3 +SiO 2 ) is 3.0% or less, and   a content of CuO is α 1 % or more,   where α 1  is a value calculated by Equation 1 below,
   α 1 =70400×exp(−2.855 ×R )  (Equation 1)
 
   and in Equation 1 above,   R is the ratio (O ion/P ion).   
     
     
         2 . A near-infrared absorbing glass,
 which comprises at least four kinds of main cations selected from the group consisting of P ions, Li ions, Cu ions, Al ions, Ba ions, Sr ions, Ca ions, Mg ions, Zn ions, K ions, Na ions, La ions, Gd ions, and Y ions,   comprises P ions, Li ions, and Cu ions as essential cations,   and comprises at least O ions as anions,   wherein   a ratio of a content of O ions relative to a content of P (O ion/P ion) ions is 3.15 or less;   in a glass composition indicated by anion %, a content of O ions is 90.0 anion % or more; and   in an oxide-based glass composition on a molar basis,   a total content of oxides of the main cations is 90.0% or more,   a total content of MgO and Al 2 O 3 (MgO+Al 2 O 3 ) is 8.0% or less,   a ratio of a total content of Na 2 O, K 2 O, and ZnO relative to a content of Li 2 O ((Na 2 O+K 2 O+ZnO)/Li 2 O) is 2.4 or less,   a total content of B 2 O 3  and SiO 2  (B 2 O 3 +SiO 2 ) is 3.0% or less, and   which satisfies Equation 2 below:
   C−3200×exp(−2.278× R )≥0  (Equation 2)
 
   and in Equation 2 above,   C is a content of CuO (units: mmol/cc) per molar volume of the glass, and   R is the ratio (O ion/P ion).   
     
     
         3 . A near-infrared absorbing glass,
 which comprises at least four kinds of main cations selected from the group consisting of P ions, Li ions, Cu ions, Al ions, Ba ions, Sr ions, Ca ions, Mg ions, Zn ions, K ions, Na ions, La ions, Gd ions, Y ions, B ions and Si ions,   comprises P ions, Li ions, and Cu ions as essential cations,   and comprises at least O ions as anions,   wherein   a ratio of a content of O ions relative to a content of P ions (O ion/P ion) is 3.15 or less;   in a glass composition indicated by anion %, a content of O ions is 90.0 anion % or more; and   in an oxide-based glass composition on a molar basis,   a total content of oxides of the main cations is 90.0% or more,   a total content of MgO and Al 2 O 3 (MgO+Al 2 O 3 ) is 8.0% or less,   a ratio of a total content of Na 2 O, K 2 O, and ZnO relative to a content of Li 2 O ((Na 2 O+K 2 O+ZnO)/Li 2 O) is 2.4 or less,   A 1 , which is calculated by Equation 3 below, is 2500 or more,
     A   1 ={O(P)−O(others)}×Cu  (Equation 3)
 
   and in Equation 3 above,   O(P) denotes an amount of oxygen that constitutes an oxide of P ions in the oxide-based glass composition,   O(others) denotes an amount of oxygen determined by subtracting the value of   O(P) from an amount of oxygen that constitutes oxides of the main cations in the oxide-based glass composition, and   Cu denotes a content of CuO on a molar basis in the oxide-based glass composition.   
     
     
         4 - 6 . (canceled) 
     
     
         7 . The near-infrared absorbing glass according to  claim 1 ,
 wherein a total content of Na 2 O and K 2 O is less than 15.0 mol %.   
     
     
         8 . The near-infrared absorbing glass according to  claim 1 ,
 wherein a content of Al 2 O 3  is less than 2.0 mol %.   
     
     
         9 . The near-infrared absorbing glass according to  claim 1 ,
 wherein a total content of Al 2 O 3 , La 2 O 3 , Y 2 O 3  and Gd 2 O 3  (Al 2 O 3 +La 2 O 3 +Y 2 O 3 +Gd 2 O 3 ) is 0.1 mol % or more.   
     
     
         10 . The near-infrared absorbing glass according to  claim 1 ,
 wherein a glass for which a half value λ T 50, which is a wavelength at which an external transmittance including reflection losses becomes 50% at a wavelength of 550 nm or longer, is 633 nm has a thickness of 0.25 mm or less, and   at the thickness, an external transmittance T600 including reflection losses at a wavelength of 600 nm is 50% or more, and an external transmittance T1200 including reflection losses at a wavelength of 1200 nm is 30% or less.   
     
     
         11 . The near-infrared absorbing glass according to  claim 1 ,
 wherein a glass for which a half value λ T 50, which is a wavelength at which an external transmittance including reflection losses becomes 50% at a wavelength of 550 nm or longer, is 633 nm has a thickness of 0.25 mm or less, and   at the thickness, an external transmittance T600 including reflection losses at a wavelength of 600 nm is 50% or more, and an external transmittance T1200 including reflection losses at a wavelength of 1200 nm is β1% or less,   β1 is a value calculated from Equation B1 below:
   β1=64× R− 170  (Equation B1)
 
   and in equation B1 above,   R is the ratio (O ion/P ion).   
     
     
         12 . The near-infrared absorbing glass according to  claim 1 ,
 wherein as transmittance characteristics calculated at a thickness of 0.11 mm, a half value λ T 50, which is a wavelength at which an external transmittance including reflection losses becomes 50%, falls within a range 600 nm to 650 nm, an external transmittance T1200 including reflection losses at a wavelength of 1200 nm is 30% or less, and an external transmittance T400 including reflection losses at a wavelength of 400 nm is 70% or more.   
     
     
         13 . The near-infrared absorbing glass according to  claim 1 ,
 wherein as transmittance characteristics calculated at a thickness of 0.21 mm, a half value λ T 50, which is a wavelength at which an external transmittance including reflection losses becomes 50%, falls within a range 600 nm to 650 nm, an external transmittance T1200 including reflection losses at a wavelength of 1200 nm is 25% or less, and an external transmittance T400 including reflection losses at a wavelength of 400 nm is 70% or more.   
     
     
         14 . The near-infrared absorbing glass according to  claim 1 ,
 wherein a glass for which a half value λ T 50, which is a wavelength at which an external transmittance including reflection losses becomes 50% at a wavelength of 550 nm or longer, is 645 nm has a thickness of 0.25 mm or less, and   at the thickness, an external transmittance T600 including reflection losses at a wavelength of 600 nm is 50% or more, and an external transmittance T1200 including reflection losses at a wavelength of 1200 nm is 30% or less.   
     
     
         15 . The near-infrared absorbing glass according to  claim 1 ,
 wherein a glass for which a half value λ T 50, which is a wavelength at which an external transmittance including reflection losses becomes 50% at a wavelength of 550 nm or longer, is 645 nm has a thickness of 0.25 mm or less, and   at the thickness, an external transmittance T600 including reflection losses at a wavelength of 600 nm is 50% or more, and an external transmittance T1200 including reflection losses at a wavelength of 1200 nm is 01% or less,   β 1  is a value calculated from equation B1 below:
   β1=64× R− 170  (Equation B1)
 
   and in equation B1 above,   R is the ratio (O ion/P ion).   
     
     
         16 . A near-infrared cut filter, which is comprised of the near-infrared absorbing glass according to  claim 1 . 
     
     
         17 . A near-infrared cut filter, which is comprised of the near-infrared absorbing glass according to  claim 2 . 
     
     
         18 . A near-infrared cut filter, which is comprised of the near-infrared absorbing glass according to  claim 3 .