Patent ID: 7438369

Claim:
An ink tank for supplying ink to recording means that ejects ink and is fixed on or removably mounted on a recording apparatus for recording input image information on a recording medium using the recording means, said ink tank comprising: a casing forming a chamber for storing the ink, said casing having a plurality of rectangular walls; an engagement member by which said ink tank engages with the recording means, said engagement member extending outwardly from a first one of said walls; a first reflecting portion having two surfaces configured to reflect an amount of incident light from outside said ink tank according to an amount of ink in said ink tank, said first reflecting portion being arranged at a predetermined position on a second one of said walls, said two surfaces being formed at predetermined angles with respect to said second wall to form a dihedral angle having a vertex line parallel to said second wall, the vertex line being parallel to a longitudinal direction of said second wall; and a second reflecting portion reflecting incident light from outside said ink tank, said second reflecting portion being arranged at a position shifted from a position of said first reflecting portion along a direction of the vertex line, wherein said second wall is different from said first wall, on which said engagement member is provided, and said engagement member has a shape projecting from said first wall in a direction parallel to the vertex line, and wherein said ink tank engages with the recording means by moving said ink tank in a direction parallel to the longitudinal direction of said second wall.