Imaging and printing system

Abstract

According to one example, there is provided an imaging system that comprises a housing, a rotatable polygon comprising multiple mirrored facets located in the housing, a laser to generate a laser beam to shine onto the polygon mirror and to reflect onto a target, and wherein, in use, the density of gas within the housing is such that turbulence-related optical distortion within the housing is not greater than a predetermined limit.

What is claimed is: 
     
         1 . A method of operating an imaging system having a rotatable polygon comprising multiple mirrored facets located in a housing and a laser to generate a laser beam to shine onto the polygon mirror and to reflect onto a target, the method comprising:
 adjusting a density of gas within the housing such that turbulence-related optical distortion within the housing is not greater than a predetermined limit; and   in the adjusted gas density, rotating the polygon mirror and selectively operating the laser in accordance with an image to be formed.   
     
     
         2 . The method of  claim 1 , further comprising, with a pump controller, operating a pump to remove gas from the housing to reduce gas pressure within the housing to limit turbulence-related optical distortion to no greater than the predetermined level. 
     
     
         3 . The method of  claim 2 , wherein the gas pressure is reduced to a level such that turbulence-related optical distortion within the housing does not adversely affect a laser beam passing through the turbulence. 
     
     
         4 . The method of  claim 1 , further comprising reducing the density of gas within the housing to below atmospheric pressure to reduce turbulence-related optical distortion within the housing. 
     
     
         5 . The method of  claim 4 , further comprising reducing the density of gas within the housing to between 0.1 and 0.2 atmospheres to reduce turbulence-related optical distortion within the housing. 
     
     
         6 . The method of  claim 1 , wherein the housing is hermetic and is filled with a lighter-than-air gas or lighter-than-air gaseous mix. 
     
     
         7 . The method of  claim 6 , further comprising reducing the density of gas within the housing to below atmospheric pressure to reduce turbulence-related optical distortion within the housing. 
     
     
         8 . The method of  claim 7 , further comprising reducing the density of gas within the housing to between 0.1 and 0.2 atmospheres to reduce turbulence-related optical distortion within the housing. 
     
     
         9 . The method of  claim 1 , wherein a portion of the housing transparent to the laser and the method further comprising generating the laser beam to shine through the transparent portion of the housing onto the polygon mirror to be scanned by the polygon mirror over a target. 
     
     
         10 . The method of  claim 1  further comprising supporting rotation of the polygon mirror in the housing on an air bearing. 
     
     
         11 . An imaging system, comprising:
 a housing;   a rotatable polygon comprising multiple mirrored facets located in the housing;   a laser to generate a laser beam to shine onto the polygon mirror and to reflect onto a target;   a pump connected to the housing through a conduit; and   a pump controller to control the pump to reduce a density of gas within the housing to a predetermined level to reduce turbulence-related optical distortion within the housing on the laser beam.   
     
     
         12 . The imaging system of  claim 11 , wherein the pump controller is to reduce the density of gas within the housing to between 0.1 and 0.2 atmospheres. 
     
     
         13 . The imaging system of  claim 11 , wherein a portion of the housing is transparent to the laser beam, and the laser is arranged to generate the laser beam to shine through the transparent portion of the housing onto the polygon mirror to be scanned by the polygon mirror over the target. 
     
     
         14 . The imaging system of  claim 11 , further comprising an air bearing supporting rotation of the polygon mirror in the sealed housing. 
     
     
         15 . The imaging system of  claim 11 , wherein the housing is hermetic and is filled with a lighter-than-air gas or lighter-than-air gaseous mix. 
     
     
         16 . A non-transitory memory comprising control instructions for an imaging system executable by a processor, the imaging system having a rotatable polygon comprising multiple mirrored facets located in a housing and a laser to generate a laser beam to shine onto the polygon mirror and to reflect onto a target, the instructions, when executed by the processor causing the processor to:
 operate a pump to adjust a density of gas within the housing such that turbulence-related optical distortion within the housing is not greater than a predetermined limit.   
     
     
         17 . The memory of  claim 16 , further comprising instruction to cause the processor to rotate the polygon mirror and selectively operate the laser in accordance with an image to be formed. 
     
     
         18 . The memory of  claim 16 , wherein the density of gas is reduced to a level such that turbulence-related optical distortion within the housing does not adversely affect the laser beam passing through the turbulence. 
     
     
         19 . The memory of  claim 16 , further comprising instruction to cause the processor to reduce the density of gas within the housing to below atmospheric pressure. 
     
     
         20 . The memory of  claim 19 , further comprising instruction to reduce the density of gas within the housing to between 0.1 and 0.2 atmospheres to reduce turbulence-related optical distortion within the housing.