Abstract: A method of forming an electrode structure for a capacitive touch sensor in a first transparent conductive layer (19) which is located on a first side of a glass substrate (5) on the second side of which is a color filter layer (11,12,13) over-coated with a transparent non-conductive layer (15) and a second transparent conductive layer (7), by a direct write laser scribing process using a pulsed solid state laser (22), the laser wavelength in the range 257 nm to 266 nm and a pulse length in the range 50 fs to 50 ns so grooves (21) are formed in the first transparent conductive layer (19) to electrically isolate areas of the first transparent conductive layer (19) on opposite sides of each groove (21). This selection of wavelength and pulse length enables the grooves (21) to be formed with substantially no damage to the underlying color filter layer (11, 12, 13), the transparent non-conductive layer (15) or the second transparent conductive layer (7) on the second side of the glass substrate (5).

Abstract: A method of forming an electrode structure for a capacitive touch sensor in a transparent conductive layer located on a transparent non-conductive layer which is located on a color filter layer by a direct write laser scribing process using a pulsed solid state laser, the laser wavelength, pulse length and beam profile at the substrate being selected to have a wavelength in the range 257 nm to 266 nm, a pulse length in the range 50 fs to 50 ns, and a top hat beam profile having a uniformity of power or energy density between a value (Emax) and a minimum value (Emin) of less than 10%, where uniformity is defined as (Emax?Emin)/(Emax+Emin). 1 Grooves can thus be formed in the transparent conductive layer to electrically isolate areas of the transparent conductive layer on opposite sides of each groove with substantially no damage to the transparent non-conductive layer or the color filter layer beneath the transparent conductive layer.

Abstract: A method of forming an electrode structure for a capacitive touch sensor in a transparent conductive layer located on a transparent non-conductive layer which is located on a colour filter layer by a direct write laser scribing process using a pulsed solid state laser, the laser wavelength, pulse length and beam profile at the substrate being selected to have a wavelength in the range 257 nm to 266 nm, a pulse length in the range 50 fs to 50 ns, and a top hat beam profile having a uniformity of power or energy density between a value (Emax) and a minimum value (Emin) of less than 10%, where uniformity is defined as (Emax?Emin)/(Emax+Emin). 1 Grooves can thus be formed in the transparent conductive layer to electrically isolate areas of the transparent conductive layer on opposite sides of each groove with substantially no damage to the transparent non-conductive layer or the colour filter layer beneath the transparent conductive layer.

Abstract: A method of forming an electrode structure for a capacitive touch sensor in a first transparent conductive layer (19) which is located on a first side of a glass substrate (5) on the second side of which is a colour filter layer (11,12,13) over-coated with a transparent non-conductive layer(15) and a second transparent conductive layer (7), by a direct write laser scribing process using a pulsed solid state laser (22), the laser wavelength in the range 257 nm to 266 nm and a pulse length in the range 50 fs to 50 ns so grooves (21) are formed in the first transparent conductive layer (19) to electrically isolate areas of the first transparent conductive layer (19) on opposite sides of each groove (21). This selection of wavelength and pulse length enables the grooves (21) to be formed with substantially no damage to the underlying colour filter layer (11, 12, 13), the transparent non-conductive layer (15) or the second transparent conductive layer (7) on the second side of the glass substrate (5).