Hair styling appliance

Abstract

A hair straightener (700) has a first arm (102) comprising a first hair contact surface and a second arm (104) comprising a second hair contact surface. The first and second hair contact surfaces are configured to capture a tress of hair between them when the first and second arms are moved towards each other in use. The hair straightener is operable in at least two of the following modes: a first mode, in which the first hair contact surface is heated more than the second hair contact surface; a second mode, in which the second hair contact surface is heated more than the first hair contact surface; and a third mode, in which both the first hair contact surface and the second hair contact surface are heated similarly.

1 . A hair straightener comprising:
 a first arm comprising a first hair contact surface; and   a second arm comprising a second hair contact surface, the second arm being coupled for movement towards the first arm, wherein the first and second hair contact surfaces are configured to capture a tress of hair between them when the first and second arms are moved towards each other in use;   the hair straightener being operable in at least two of the following modes:   a first mode, in which the first hair contact surface is heated more than the second hair contact surface;   a second mode, in which the second hair contact surface is heated more than the first hair contact surface; and   a third mode, in which both the first hair contact surface and the second hair contact surface are heated similarly.   
     
     
         2 . The hair straightener of  claim 1 , wherein, in the first mode, only the first hair contact surface is heated, and in the second mode, only the second hair contact surface is heated. 
     
     
         3 . The hair straightener of  claim 1 , comprising at least one sensor for sensing a position and/or orientation of the hair straightener, the hair straightener being configured to operate in one of the modes responsive to the hair straightener being in a first position and/or orientation as sensed by the at least one sensor. 
     
     
         4 . The hair straightener of  claim 3 , the hair straightener being configured to operate in another of the modes responsive to the hair straightener being in a second position and/or orientation as sensed by the at least one sensor, the second position and/or orientation being different to the first position and/or orientation. 
     
     
         5 . The hair straightener of  claim 4 , wherein the first and/or the second position and/or orientation comprises a range of positions and/or orientations. 
     
     
         6 . The hair straightener of  claim 3 , wherein the at least one sensor comprises at least one light sensor, and the hair straightener is configured to operate in the first or the second mode, such that whichever of the first hair contact surface and the second hair contact surface is closer to a user's head is heated, and the other of the first hair contact surface and the second hair contact surface is unheated. 
     
     
         7 . The hair straightener of  claim 6 , wherein the at least one light sensor comprises at least:
 a first light sensor disposed to sense light levels on a side of the hair straightener corresponding to the first arm; and   a second light sensor disposed to sense light levels on a side of the hair straightener corresponding to the second arm;   the first and second light sensors allowing determination of which of the first hair contact surface and the second hair contact surface is closer to a user's head.   
     
     
         8 . The hair straightener of  claim 7 , wherein the first light sensor is disposed on the first arm and the second light sensor is disposed on the second arm. 
     
     
         9 . The hair straightener of  claim 3 , wherein the at least one sensor comprises an inertial measurement unit. 
     
     
         10 . The hair straightener of  claim 3 , wherein the at least one sensor comprises an accelerometer. 
     
     
         11 . The hair straightener of  claim 1 , operable in only two of the first, second, and third modes. 
     
     
         12 . A method of operating a hair straightener, the hair straightener comprising: a first arm comprising a first hair contact surface;
 a first heater configured for heating the first hair contact surface;   a second arm comprising a second hair contact surface, the second arm being coupled for movement towards the first arm, wherein the first and second hair contact surfaces are configured to capture a tress of hair between them when the first and second arms are moved towards each other in use;   a second heater configured for heating the second hair contact surface; and   at least one position and/or orientation sensor;   the method comprising:   sensing, using the at least one position and/or orientation sensor, a position and/or orientation of the hair straightener;   responsive to the sensed position and/or orientation, operating the hair straightener in a first mode in which the first heater heats the first hair contact surface more than the second heater heats the second hair contact surface;   sensing, using the at least one position and/or orientation sensor, a change in the position and/or orientation of the hair straightener; and   responsive to the sensed position and/or orientation, operating the hair straightener in a second mode in which the second heater heats the second hair contact surface more than the first heater heats the first hair contact surface.   
     
     
         13 . The method of  claim 12 , wherein operating the hair straightener in the first mode comprises heating only the first hair contact surface. 
     
     
         14 . The method of  claim 12 , wherein operating the hair straightener in the second mode comprises heating only the second hair contact surface.