Image input apparatus, image input method, personal authentication apparatus, and electronic apparatus

• US 8,085,312 B2
• Filed: 10/05/2007
• Issued: 12/27/2011
• Est. Priority Date: 10/12/2006
• Status: Expired due to Fees

• Current Assignee: Ricoh Company Limited
• Original Assignee: Ricoh Company Limited
• Inventors: Morita, Nobuhiro, Yamanaka, Yuji, Iseki, Toshiyuki, Nasukawa, Toshimichi, Kosuga, Shinichi, Takahashi, Hiroaki, Takahashi, Akira
• Primary Examiner(s): Tran, Sinh
• Assistant Examiner(s): BERARDESCA, PAUL M
• Application Number:
  US12/096,625
• Publication Number:
  US 20080316323A1
• Time in Patent Office: 1,544 Days
• Field of Search: 348/264, 348/222.1, 348/340
• US Class Current: 348/222.1
• CPC Class Codes: A61B 5/0059 using light, e.g. diagnosis by transillumination, diascopy, fluorescence A61B5/0093, A61B5/1455, A61B5/02416 and A61B5/0261 take precedence
• CPC Class Codes: A61B 5/1172 using fingerprinting
• CPC Class Codes: G06T 1/0007 Image acquisition
• CPC Class Codes: G06V 40/1318 using electro-optical elements or layers, e.g. electroluminescent sensing
• CPC Class Codes: G06V 40/14 Vascular patterns
• CPC Class Codes: H04N 5/2628 Alteration of picture size, shape, position or orientation, e.g. zooming, rotation, rolling, perspective, translation

Abstract

An image input apparatus that inputs an image of an object residing within a living body is disclosed. The image input apparatus includes a light source that irradiates near infrared light on the living body, a lens array arranged at a position facing the living body and including plural lenses each having a face with zero or negative power arranged at a side facing the living body and a face with positive power arranged at a side facing an image surface, an imaging unit arranged at the image surface side of the lens array that forms a compound-eye image corresponding to a collection of ommatidium images formed by the lenses of the lens array, and a reconstruction unit that reconstructs a single image from the compound-eye image using a parallax between the ommatidium images. The reconstructed single image is input as the image of the object.

Claims

1. An image input apparatus that inputs an image of an object residing within a living body, the apparatus comprising:

a light source that irradiates near infrared light on the living body;

a lens array that is arranged at a position facing the living body and includes a plurality of lenses, each of the lenses having a face with zero or negative power arranged at a side facing the living body and a face with positive power arranged at a side facing an image surface;

an imaging unit that is arranged at the image surface side of the lens array and is configured to form a compound-eye image corresponding to a collection of ommatidium images formed by the lenses of the lens array;

a bias component removal processing unit that is configured to generate a compound-eye image in which a bias component, due to light other than the near infrared light irradiated by the light source, is removed, the bias component being generated based on a difference between a compound-eye image formed by the imaging unit while the light source is turned ON and a compound-eye image is formed by the imaging unit while the light source is turned OFF; and

a reconstruction unit that is configured to select a reference ommatidium image, obtain parallaxes of the ommatidium images with respect to the reference ommatidium image, and reconstruct the ommatidium images from the compound-eye image generated by the bias component removal processing unit based on the obtained parallaxes, said reconstructed ommatidium images being input as the image of the object.

2. The image input apparatus as claimed in claim 1, further comprising:

an optical band pass filter that is configured to pass light having a wavelength within a predetermined wavelength range including a wavelength of the near infrared light irradiated by the light source, said optical band pass filter being arranged at the living body side or the image surface side of the lens array.

3. The image input apparatus as claimed in claim 1, further comprising:

a transparent plate for adjusting a distance between the object and the lens array wherein the transparent plate is arranged at the living body side of the lens array.

4. The image input apparatus as claimed in claim 1, further comprising:

a light shielding member that prevents occurrence of crosstalk between the lenses of the lens array at the image surface side.

5. An image input apparatus that inputs an image of an object residing within a living body, the apparatus comprising:

a light source that irradiates near infrared light on the living body;

a lens array that is arranged at a position facing the living body and includes a plurality of lenses, each of the lenses having a face with zero or negative power at a side facing the living body and a face with positive power at a side facing an image surface;

an imaging unit that is arranged on the image surface side of the lens array and is configured to form a compound-eye image corresponding to a collection of ommatidium images formed by the lenses of the lens array;

a bias component removal processing unit is configured to generate a compound-eye image in which a bias component, due to light other than the near infrared light irradiated by the light source, is removed, the bias component being generated based on a difference between a compound-eye image formed by the imaging unit while the light source is turned ON and a compound-eye image formed by the imaging unit while the light source is turned OFF;

a correction unit is configured to correct image degradation caused by the lenses in the ommatidium images of the compound-eye image generated by the bias component removal processing unit based on optical transfer function data pertaining to the lenses that are prepared beforehand and generate a corrected compound-eye image; and

a reconstruction unit that is configured to select a reference ommatidium image, obtain parallaxes of the ommatidium images with respect to the reference ommatidium image, and reconstruct the ommatidium images from the corrected compound-eye image generated by the correction unit based on the obtained parallaxes, said reconstructed ommatidium images being input as the image of the object.

6. The image input apparatus as claimed in claim 5, further comprising:

an optical band pass filter that is configured to pass light having a wavelength within a predetermined wavelength range including a wavelength of the near infrared light irradiated by the light source, said optical band pass filter being arranged at the living body side or the image surface side of the lens array.

7. The image input apparatus as claimed in claim 5, further comprising:

a distance detecting unit that is configured to detect a distance between the living body and the lens array;

wherein the correction unit selects a set of optical transfer function data from the optical transfer function data pertaining to the lenses that are prepared beforehand according to the distance detected by the distance detecting unit and uses the selected set of optical transfer function data for correcting the image degradation caused by the lenses.

8. The image input apparatus as claimed in claim 7, wherein

the distance detecting unit detects the distance based on the parallax between the ommatidium images of the compound-eye image formed by the imaging unit.

9. The image input apparatus as claimed in claim 5, further comprising:

a transparent plate for adjusting a distance between the object and the lens array wherein the transparent plate is arranged at the living body side of the lens array.

10. The image input apparatus as claimed in claim 5, further comprising:

a light shielding member that prevents occurrence of crosstalk between the lenses of the lens array at the image surface side.

11. An image input method for inputting an image of an object residing within a living body, using an imaging optical system that includes:

a light source that irradiates near infrared light on the living body, a lens array that is arranged at a position facing the living body and includes a plurality of lenses, each of the lenses having a face with zero or negative power at a side facing the living body and a face with positive power at a side facing an image surface, and an imaging unit that is arranged on the image surface side of the lens array and is configured to form a compound-eye image corresponding to a collection of ommatidium images formed by the lenses of the lens array, the method comprising;

generating, using a bias component removal processing unit, a compound-eye image in which a bias component, due to light other than the near infrared light irradiated by the light source, is removed, the bias component being generated based on a difference between a compound-eye image formed by the imaging unit while the light source is turned ON and a compound-eye image formed by the imaging unit while the light source is turned OFF;

correcting image degradation caused by the lenses in the ommatidium images of the compound-eye image formed by the generated by the bias component removal processing unit based on optical transfer function data pertaining to the lenses that are prepared beforehand to generate a corrected compound-eye image;

selecting a reference ommatidium image;

obtaining parallexes of the ommatidium images with respect to the reference ommatidium image;

reconstructing the ommatidium images from the corrected compound-eye image based on the obtained parallaxes; and

inputting the reconstructed ommatidium images as the image of the object.