Lens array unit, image sensor unit, image reading apparatus, image forming apparatus, and method of manufacturing lens array unit

An image sensor unit comprising:

• a lens array unit comprising:
• a lens array comprising a plurality of lenses, a first side plate, and a second side plate, the plurality of lenses being arrayed in an array direction, the first side plate and the second side plate being configured to hold the plurality of lenses therebetween;
• and
• a frame made of resin and comprising a first supporting portion and a second supporting portion, the first supporting portion being in contact with an outside surface of the first side plate, the second supporting portion being in contact with an outside surface of the second side plate, the first supporting portion and the second supporting portion being configured to hold the lens array therebetween and support the lens array;
• and
• an image sensor configured to receive light focused by the lens array of the lens array unit such that an image is formed on the image sensor,
• wherein the outside surface of the first side plate comprises a plurality of first concave portions spaced from each other in the array direction and configured to fit with the first supporting portion.

An image reading apparatus comprising:

• a document platen on which a document is placed;
• and
• an image sensor unit configured to read an image of the document placed on the document platen,
• wherein an image sensor unit comprises
• a lens array unit comprising:
• a lens array comprising a plurality of lenses, a first side plate, and a second side plate, the plurality of lenses being arrayed in an array direction, the first side plate and the second side plate being configured to hold the plurality of lenses therebetween;
• and
• a frame made of resin and comprising a first supporting portion and a second supporting portion, the first supporting portion being in contact with an outside surface of the first side plate, the second supporting portion being in contact with an outside surface of the second side plate, the first supporting portion and the second supporting portion being configured to hold the lens array therebetween and support the lens array;
• and
• an image sensor configured to receive light focused by the lens array of the lens array unit such that an image is formed on the image sensor, and
• wherein the outside surface of the first side plate comprises a plurality of first concave portions spaced from each other in the array direction and configured to fit with the first supporting portion.

An image forming apparatus comprising:

• an image reading apparatus;
• and
• an image forming portion configured to form an image on a recording medium in accordance with image information that is read by the image reading apparatus,
• wherein an image reading apparatus comprises
• a document platen on which a document is placed;
• and
• an image sensor unit configured to read an image of the document placed on the document platen,
• wherein an image sensor unit comprises
• a lens array unit comprising:
• a lens array comprising a plurality of lenses, a first side plate, and a second side plate, the plurality of lenses being arrayed in an array direction, the first side plate and the second side plate being configured to hold the plurality of lenses therebetween;
• and
• a frame made of resin and comprising a first supporting portion and a second supporting portion, the first supporting portion being in contact with an outside surface of the first side plate, the second supporting portion being in contact with an outside surface of the second side plate, the first supporting portion and the second supporting portion being configured to hold the lens array therebetween and support the lens array;
• and
• an image sensor configured to receive light focused by the lens array of the lens array unit such that an image is formed on the image sensor, and
• wherein the outside surface of the first side plate comprises a plurality of first concave portions spaced from each other in the array direction and configured to fit with the first supporting portion.

A method of manufacturing a lens array unit, the method comprising:

• forming a lens array comprising a plurality of lenses, a first side plate, and a second side plate, the plurality of lenses being arrayed in an array direction, the first side plate and the second side plate being configured to hold the plurality of lenses therebetween;
• and
• forming a frame by setting the lens array in a mold and injecting resin material into the mold, the frame comprising a first supporting portion and a second supporting portion, the first supporting portion being in contact with an outside surface of the first side plate, the second supporting portion being in contact with an outside surface of the second side plate, the first supporting portion and the second supporting portion being configured to hold the lens array therebetween and support the lens array,
• wherein the forming of the lens array comprises forming a plurality of first concave portions in the outside surface of the first side plate, with the plurality of first concave portions being spaced from each other in the array direction, and
• wherein the forming of the frame comprises forming the first supporting portion such that the first supporting portion fits in the plurality of first concave portions.