What is the factors that cause the invention of laser printer to be happened? -

Can anyone tell me what is the situation and needs that cause the invention of laser printer to be happened? why Gary Starkweather invented the laser printer? what is the factors? i cant find the answer anywhere.. i really need your help.. i will appreciate it.. ^^

the urge of industrial revolution did it ! Introduction Laser printers were once called quot;page printersquot; because they print entire pages at a time and not a dot at a time like ink jet or dot matrix printers. Considered to be the fastest type of printer on the market, the laser printer is also significantly more expensive. The power behind the laser printer is the mixing of six different mechanisms: electricity, optics, chemistry, heat, friction and magnetism. A Xerox researcher, Gary Starkweather, invented the laser printer in 1976. The printer capitalized on the same xerographic process that Xerox used in their photocopiers. The only difference was the placement of the laser on the inside of the printer. The laser printer developed over the years and is now used in homes and offices all over the world. Raster Image Processing A raster line, or scan line, is the horizontal line of dots across every printed page. The raster image processor (RIP) is the mechanism that is responsible for creating the image before it is printed. The RIP is in charge of generating a bitmap of every page sent to the printer. It then signals the printer to begin the printing process once each page has been stored in raster memory. Charging the Print Drum An electric charge is sent to the print drum by the corona wire. The drum is given a negative charge of -600Vdc. The drum is a photosensitive cylinder that is made with a silicon coating. It is able to hold the charge because of the photocharging layer underneath the silicon. Exposing After the drum is properly charged, a laser moves across the rotating polygonal mirror above the drum. As the drum rotates, the page that is to be printed is encoded into the photoreceptor and then directly onto the drum. The laser moves across the drum in a strobe-like manner until the entire page is printed onto it. While it does the job, the laser also neutralizes the negative charge for any white space so that the toner is only attracted to the parts that make up the image. Developing The image on the drum is then exposed to the toner (a black chalk-like substance made of carbon, polyester and iron particles). The toner is also given a negative charge so that it can be attracted electrostatically to the image imprinted on the drum. The more charge given to the toner, the darker the image will be. Transferring The paper is pulled into the machine by the paper feeder, where it travels through a predefined path called the paper transport path. The paper is charged positively to +600Vdc, the exact opposite of the drum. The two conflicting charges are what transfer the image onto the paper once it passes under the drum. Fusing The image is then fused onto the paper by the heat from the fuser. The fuser is made up of two rollers: a hollow heat roller and a rubber pressure one. As the paper passes between the two rollers, the combination of heat and pressure is supplied, and the toner is fused into the paper. Cleaning To keep the toner from collecting on the drum, it is cleaned after every print job. The cleaning blade brushes off any excess toner and deposits it in the waste reservoir. After this, any remaining charge to the drum is removed by a discharge lamp. The machine is now ready for the next print job.