Field lens for an electrophotographic printing machine

Claim 2

An electrophotographic printing machine, including: a photoconductive member; means for charging at least a portion of said photoconductive member to a substantially uniform level; means for illuminating an opaque original document; a field lens having the opaque original document disposed thereon in a light receiving relationship with light rays transmitted from said illuminating means; and means for forming a light image of the opaque original document and irradiating the charged portion of said photoconductive member therewith to record thereon an electrostatic latent image of the original document.

Claim 5

An apparatus as recited in claim 2, wherein said cover member includes: a substantially rigid outer shell; and a resilient sheet member secured to said outer shell, said resilient sheet member being positioned to contact the original document disposed on said field lens in the closed position.

Claim 6

An apparatus as recited in claim 3, further including resilient means secured to said frame member on the periphery of the aperture therein with said field lens being mounted on said resilient means in the aperture of said frame member.

Claim 7

An apparatus as recited in claim 2, wherein said field lens includes preferably 200 gratings per inch.

Claim 8

An electrophotographic printing machine for reproducing an opaque original document or a transparency, including: a photoconductive member; means for charging at least a portion of said photoconductive member to a substantially uniform level; means for illuminating the opaque original document; a field lens arranged to support the opaque original document in a light receiving relationship with light rays transmitted from said illuminating means; a substantially rigid frame member having an aperture therein, said frame member being mounted in the aperture of the printing machine; resilient means secured to said frame member on the periphery of the aperture therein with said field lens being mounted on said resilient means in the aperture of said frame member; means for forming a light image of the opaque original document and irradiating the charged portion of said photoconductive member therewith to record thereon an electrostatic latent image of the original document; means for projecting a light image of the transparency through said field lens onto the charged portion of said photoconductive member to record thereon an electrostatic latent image of the transparency, said projecting means being inoperative during the reproduction of the original document; means for modulating the light image of the transparency; and a composition frame disposed on said field lens in a light receiving relationship with said illuminating means when said projecting means is operative, said forming means exposing the charged portion of said photoconductive member to a light image of said composition frame recording thereon a combined electrostatic latent image comprising the electrostatic latent image of the transparency and the electrostatic latent image of said composition frame.

Claim 9

An electrophotographic printing machine for reproducing an opaque original document or a transparency, including: a photoconductive member; means for charging at least a portion of said photoconductive member to a substantially uniform level; means for illuminating the opaque original document; a field lens arranged to support the opaque original document in a light receiving relationship with light rays transmitted from said illuminating means; a substantially rigid frame member having an aperture therein, said frame member being mounted in the aperture of the printing machine; resilient means secured to said frame member on the periphery of the aperture therein with said field lens being mounted on said resilient means in the aperture of said frame member; means for forming a light image of the opaque original document and irradiating the charged portion of said photoconductive member therewith to record thereon an electrostatic latent image of the original document; means for projecting a light image of the transparency through said field lens onto the charged portion of said photoconductive member to record thereon an electrostatic latent image of the transparency, said projecting means being inoperative during the reproduction of the original document; means for modulating the light image of the transparency; and a composition frame disposed on said field lens in a light receiving relationship with said illuminating means when said projecting means is operative, said forming means exposing the charged portion of said photoconductive member to a light image of said composition frame recording thereon a combined electrostatic latent image comprising the electrostatic latent image of the transparency and the electrostatic latent image of said composition frame.

Claim 10

A printing machine as recited in claim 6, further including a cover member mounted movably on said frame member, said cover member being mounted movably from an opened position permitting the original document to be disposed on said field lens or the transparency to be copied and to a closed position securing releasably thereon the original document.

Claim 11

A printing machine as recited in claim 7, wherein said cover member includes: a substantially rigid outer shell; and a resilient sheet member secured to said outer shell, said resilient sheet member being positioned to contact said composition frame disposed on said field lens in the closed position.

Claim 12

A printing machine as recited in claim 6, wherein said field lens includes preferably 200 gratings per inch.

Claim 13

A printing machine as recited in claim 6, wherein said projecting means includes a slide projector arranged to project a light image of the transparency through said field lens.

Claim 14

A printing machine as recited in claim 10, wherein said modulating means includes a screen interposed between said field lens and said composition frame.

Claim 15

A printing machine as recited in claim 11, wherein said forming means includes a lens.

Claim 16

A printing machine as recited in claim 12, wherein said screen member includes a plurality of spaced, soft gray square dots.

Claim 17

A printing machine as recited in claim 13, wherein said screen member preferably includes 85 dots per inch.

Claim 18

A printing machine as recited in claim 14, further including means for filtering the light image of the original document to form a single color light image which irradiates the charged portion of said photoconductive member to record thereon a single color electrostatic latent image.

Claim 19

A printing machine as recited in claim 15, further including: means for developing the single color electrostatic latent image recorded on said photoconductive member with toner particles complementary in color to the color of the single color light image; means for transferring the toner powder image from the electrostatic latent image recorded on said photoconductive member to a sheet of support material; and means for permanently affixing the toner powder image to the sheet of support material.