A mobile communication terminal comprising: a housing (110;210;310); a first circuit board (120;220; 320) fixed to the housing; a second circuit board (130; 230;330) overlapped with at least a portion with the first circuit board and fixed to the housing; and an electrical connector configured to electronically connect the first circuit board and the second circuit board, wherein the housing comprises a window (112;212;312), wherein the first circuit board (130;230;330) comprises a display panel (122;222;322) mounted on the first circuit board and configured to display an image, and wherein the display panel (122;222;322) of the first circuit board is attached to the window of the housing and the housing comprises a button indicator part (113; 213;313) associated with a plurality of touch buttons, wherein the first circuit board (130;230;330) comprises circuitry configured to perform a function according to a touch induced in the second circuit board corresponding to a selected one of the plurality of touch buttons, wherein mounting structure comprises a touch sensor configured to receive the touch, and wherein the touch sensor comprises: an opening (134;234;334) not covering the button indicator part of the housing; an electrode surface (132;232;332) constructed around the opening associated with the respective touch buttons; a Printed Circuit Board, PCB, or Flexible PCB, FPCB, comprising a circuit connected to the electrode surface; and a light guide film (133;233;333) arranged to conduct light emitted from a light source (136;236;336) to the opening. a housing (110;210;310); a first circuit board (120;220; 320) fixed to the housing; a second circuit board (130; 230;330) overlapped with at least a portion with the first circuit board and fixed to the housing; and an electrical connector configured to electronically connect the first circuit board and the second circuit board, wherein the housing comprises a window (112;212;312), wherein the first circuit board (130;230;330) comprises a display panel (122;222;322) mounted on the first circuit board and configured to display an image, and wherein the display panel (122;222;322) of the first circuit board is attached to the window of the housing and the housing comprises a button indicator part (113; 213;313) associated with a plurality of touch buttons, wherein the first circuit board (130;230;330) comprises circuitry configured to perform a function according to a touch induced in the second circuit board corresponding to a selected one of the plurality of touch buttons, wherein mounting structure comprises a touch sensor configured to receive the touch, and wherein the touch sensor comprises: an opening (134;234;334) not covering the button indicator part of the housing; an electrode surface (132;232;332) constructed around the opening associated with the respective touch buttons; a Printed Circuit Board, PCB, or Flexible PCB, FPCB, comprising a circuit connected to the electrode surface; and a light guide film (133;233;333) arranged to conduct light emitted from a light source (136;236;336) to the opening. an opening (134;234;334) not covering the button indicator part of the housing; an electrode surface (132;232;332) constructed around the opening associated with the respective touch buttons; a Printed Circuit Board, PCB, or Flexible PCB, FPCB, comprising a circuit connected to the electrode surface; and a light guide film (133;233;333) arranged to conduct light emitted from a light source (136;236;336) to the opening.