Information reading device
An information reading device may include a transparent placement member, a first illumination part, a second illumination part, a first optical system structured to read information on the medium, a second optical system structured to read another information on the medium, a housing formed with a medium insertion port and in which the placement member, the first illumination part, the second illumination part, the first optical system and the second optical system are accommodated, and a semi-light shielding member having a semi-light shielding part which transmits light of a part of a wavelength region and blocks lights of other wavelength regions and covers at least an upper side of the medium insertion port. A transmittance curve indicating a relationship between transmittance of light and a wavelength of the semi-light shielding part is a curve having a peak within a wavelength region of visible light.
1. An information reading device structured to optically read information recorded on an information recording medium, the information reading device comprising:
a transparent placement member on which the information recording medium is placed;
a first illumination part which emits light on an under face of the information recording medium placed on the placement member;
a second illumination part which emits light on an upper face of the information recording medium placed on the placement member;
a first optical system structured to read information recorded on the under face of the information recording medium placed on the placement member;
a second optical system structured to read information recorded on the upper face of the information recording medium placed on the placement member;
a housing comprising a front face formed with a medium insertion port into which the information recording medium is inserted, and the housing accommodating the placement member, the first illumination part, the second illumination part, the first optical system and the second optical system; and
a semi-light shielding member comprising a semi-light shielding part which transmits light of a part of a wavelength region and blocks lights of other wavelength regions and covers at least an upper side of the medium insertion port;
wherein a transmittance curve indicating a relationship between transmittance of light and a wavelength of the semi-light shielding part is a curve having a peak within a wavelength region of visible light.
2. The information reading device according to claim 1 , wherein the semi-light shielding member is movable with respect to the housing between a light shielding position where the semi-light shielding part covers an upper side and a front side of the medium insertion port and an open position where at least the front side of the medium insertion port is opened.
3. The information reading device according to claim 2 , wherein the semi-light shielding part comprises a cut-out part structured to prevent an interference of a hand of an operator pressing down the information recording medium placed on the placement member from an upper side with the semi-light shielding part when the semi-light shielding member is located at the light shielding position.
4. The information reading device according to claim 3 , wherein the transmittance curve has only one peak within a wavelength region of visible light.
5. The information reading device according to claim 4 , wherein the transmittance curve has a peak within a wavelength region from 500 nm to 560 nm.
6. The information reading device according to claim 5 , wherein a half-value width of the peak of the transmittance curve is 80 nm or less.
7. The information reading device according to claim 4 , wherein a half-value width of the peak of the transmittance curve is 80 nm or less.
8. The information reading device according to claim 2 , wherein the transmittance curve has only one peak within a wavelength region of visible light.
9. The information reading device according to claim 8 , wherein the transmittance curve has a peak within a wavelength region from 500 nm to 560 nm.
10. The information reading device according to claim 9 , wherein a half-value width of the peak of the transmittance curve is 80 nm or less.
11. The information reading device according to claim 8 , wherein a half-value width of the peak of the transmittance curve is 80 nm or less.
12. The information reading device according to claim 1 , wherein the transmittance curve has only one peak within a wavelength region of visible light.
13. The information reading device according to claim 12 , wherein the transmittance curve has a peak within a wavelength region from 500 nm to 560 nm.
14. The information reading device according to claim 13 , wherein a half-value width of the peak of the transmittance curve is 80 nm or less.
15. The information reading device according to claim 12 , wherein a half-value width of the peak of the transmittance curve is 80 nm or less.