1. An image forming apparatus, comprising:
a plurality of image forming stations; and
a control portion configured to control an image forming operation,
each of the plurality of image forming stations comprising:
an image bearing member configured to form a toner image on a surface thereof; and
a charging device configured to charge the image bearing member,
wherein respective toner images formed on image bearing members of the plurality of image forming stations are sequentially transferred to a transfer incurring member so as to be superimposed on top of each other, and
wherein the control portion sets a voltage applied to the charging device in forming an image in an image forming station among the plurality of image forming stations which performs a transfer later, based on image density information of the toner image transferred to the transfer incurring member by an image forming station among the plurality of image forming stations which performs a transfer earlier in a sequence of image forming operations.
2. An image forming apparatus according to claim 1, wherein the control portion sets the voltage applied to the charging device in forming the image in an image forming station among the plurality of image forming stations which performs the transfer later to a first set value when the image density information of the toner image transferred to the transfer incurring member by an image forming station among the plurality of image forming stations which performs the transfer earlier does not satisfy a predetermined high density condition, and to a second set value when the image density information satisfies the predetermined high density condition in the sequence of the image forming operations, and
wherein an absolute value of the applied voltage in the second set value is larger than an absolute value of the applied voltage in the first set value.
3. An image forming apparatus according to claim 2, wherein the control portion determines that the predetermined high density condition is satisfied when the toner image transferred to the transfer incurring member by the image forming station among the plurality of image forming stations which performs the transfer earlier includes a pixel having a predetermined density or higher.
4. An image forming apparatus according to claim 2, wherein the control portion determines that the predetermined high density condition is satisfied when a total number of pixels having a predetermined density or higher included in the toner image transferred to the transfer incurring member by the image forming station among the plurality of image forming stations which performs the transfer earlier is equal to or larger than a predetermined number.
5. An image forming apparatus according to claim 2, wherein the control portion determines that the predetermined high density condition is satisfied when a total number of pixels, among pixels in the toner image transferred to the transfer incurring member by the image forming station among the plurality of image forming stations which performs the transfer earlier, which have a predetermined density or higher and pixels adjacent to which also have the predetermined density or higher is equal to or larger than a predetermined number.
6. An image forming apparatus according to claim 1, further comprising an exposure device configured to expose the image bearing members to form latent images on the image bearing members,
wherein each of the plurality of image forming stations further comprises a developing device configured to develop the latent image to form the toner image on the image bearing member.
7. An image forming apparatus according to claim 6, wherein the exposure device sets, by exposing an image section and a non-image section of the image bearing member charged by the charging device at different exposure intensities, surface potentials of the image section and the non-image section to a predetermined image section potential and a predetermined non-image section potential, respectively.
8. An image forming apparatus according to claim 6, wherein an exposure intensity of the exposure device which exposures the image bearing member is controlled in accordance with the voltage applied to the charging device configured to charge the image bearing member.
9. An image forming apparatus, comprising:
a plurality of image forming stations; and
a control portion configured to control an image forming operation,
each of the plurality of image forming stations comprising:
an image bearing member configured to form a toner image on a surface thereof; and
a charging device configured to charge the image bearing member,
the image forming apparatus further comprising an exposure device configured to expose an image section and a non-image section of the image bearing member charged by the charging device at different exposure intensities to set surface potentials of the image section and the non-image section to a predetermined image section potential and a predetermined non-image section potential, respectively,
wherein respective toner images formed on image bearing members of the plurality of image forming stations are sequentially transferred to a transfer incurring member so as to be superimposed on top of each other, and
wherein the control portion sets a voltage applied to the charging device and the exposure intensities of the image section and the non-image section by the exposure device in forming an image in an image forming station among the plurality of image forming stations which performs a transfer later to first set values when image density information of the toner image transferred to the transfer incurring member by an image forming station among the plurality of image forming stations which performs a transfer earlier does not satisfy a predetermined high density condition, and to second set values when the image density information satisfies the predetermined high density condition in a sequence of image forming operations.
10. An image forming apparatus according to claim 9, wherein an absolute value of a charged potential formed by the voltage of a second set value being applied to the charging device is larger than an absolute value of a charged potential formed by the voltage of a first set value being applied to the charging device.
11. An image forming apparatus according to claim 9, wherein the exposure intensities in the first set values and the exposure intensities in the second set values are set so that image section potentials formed by respective exposures have the same value and non-image section potentials formed by the respective exposures have the same value.
12. An image forming apparatus according to claim 9, wherein exposure at the first set values excludes exposure of the non-image section.
13. An image forming apparatus according to claim 9, wherein the control portion determines that the predetermined high density condition is satisfied when the toner image transferred to the transfer incurring member by the image forming station among the plurality of image forming stations which performs the transfer earlier includes a pixel having a predetermined density or higher.
14. An image forming apparatus according to claim 9, wherein the control portion determines that the predetermined high density condition is satisfied when a total number of pixels having a predetermined density or higher included in the toner image transferred to the transfer incurring member by the image forming station among the plurality of image forming stations which performs the transfer earlier is equal to or larger than a predetermined number.
15. An image forming apparatus according to claim 9, wherein the control portion determines that the predetermined high density condition is satisfied when a total number of pixels, among pixels in the toner image transferred to the transfer incurring member by the image forming station among the plurality of image forming stations which performs the transfer earlier, which have a predetermined density or higher and pixels adjacent to which also have a predetermined density or higher is equal to or larger than a predetermined number.
16. An image forming apparatus according to claim 9, wherein each of the plurality of image forming stations further comprises a developing device configured to make toner adhere to the image section of the image bearing member to form the toner image.
The claims below are in addition to those above.
All refrences to claim(s) which appear below refer to the numbering after this setence.
1. An integrated laser apparatus comprising:
an array of beam emitters each emitting an input beam; and
a glass substrate optically coupled to the array of beam emitters, portions of the substrate defining:
(i) a plurality of input waveguides for receiving the input beams from the array of beam emitters and propagating the beams over the substrate,
(ii) focusing optics for receiving the beams from the input waveguides and converging the received beams toward a dispersive element,
(iii) a dispersive element for receiving the converged beams and dispersing the converged beams, thereby forming a dispersed beam, and
(iv) an output waveguide for receiving the dispersed beam from the dispersive element, an output facet of the output waveguide (a) comprising a portion of an exterior surface of the substrate, and (b) forming a partially reflective output coupler that (A) transmits a first portion of the dispersed beam as a multi-wavelength output beam and (B) reflects a second portion of the dispersed beam back toward the dispersive element and the array of beam emitters, thereby forming an external cavity that stabilizes each of the input beams at a different wavelength.
2. The integrated laser apparatus of claim 1, wherein the substrate comprises fused silica or quartz.
3. The integrated laser apparatus of claim 1, wherein an OH content of the substrate is less than 5 ppm.
4. The integrated laser apparatus of claim 1, wherein a concentration of metallic impurities in the substrate is less than 5 ppm.
5. The integrated laser apparatus of claim 1, further comprising a partially reflective coating disposed on the output facet of the output waveguide.
6. The integrated laser apparatus of claim 1, wherein the array of beam emitters is butt-coupled to the substrate.
7. The integrated laser apparatus of claim 6, further comprising an index-matching material disposed between the array of beam emitters and the substrate.
8. The integrated laser apparatus of claim 1, wherein an input facet of each of the input waveguides comprises a portion of an exterior surface of the substrate.
9. The integrated laser apparatus of claim 8, further comprising an anti-reflection coating on the input facet of each of the input waveguides.
10. An integrated laser apparatus comprising:
an array of beam emitters each emitting an input beam; and
a glass substrate optically coupled to the array of beam emitters, portions of the substrate defining:
(i) a plurality of input waveguides for receiving the input beams from the array of beam emitters and propagating the beams over the substrate, wherein at least portions of the input waveguides are mutually angled andor curved to overlap the input beams at a point proximate a dispersive element,
(ii) a dispersive element for receiving the overlapped beams and dispersing the overlapped beams, thereby forming a dispersed beam, and
(iii) an output waveguide for receiving the dispersed beam from the dispersive element, an output facet of the output waveguide (a) comprising a portion of an exterior surface of the substrate, and (b) forming a partially reflective output coupler that (A) transmits a first portion of the dispersed beam as a multi-wavelength output beam and (B) reflects a second portion of the dispersed beam back toward the dispersive element and the array of beam emitters, thereby forming an external cavity that stabilizes each of the input beams at a different wavelength.
11. The integrated laser apparatus of claim 10, wherein an optical path between the input waveguides and the dispersive element is free of focusing optics.
12. The integrated laser apparatus of claim 10, wherein the substrate comprises fused silica or quartz.
13. The integrated laser apparatus of claim 10, wherein an OH content of the substrate is less than 5 ppm.
14. The integrated laser apparatus of claim 10, wherein a concentration of metallic impurities in the substrate is less than 5 ppm.
15. The integrated laser apparatus of claim 10, further comprising a partially reflective coating disposed on the output facet of the output waveguide.
16. The integrated laser apparatus of claim 10, wherein the array of beam emitters is butt-coupled to the substrate.
17. The integrated laser apparatus of claim 16, further comprising an index-matching material disposed between the array of beam emitters and the substrate.
18. The integrated laser apparatus of claim 10, wherein an input facet of each of the input waveguides comprises a portion of an exterior surface of the substrate.
19. The integrated laser apparatus of claim 18, further comprising an anti-reflection coating on the input facet of each of the input waveguides.
20. An apparatus for producing a multi-wavelength output beam from beams emitted by an array of beam emitters, the apparatus comprising a glass substrate, portions of the substrate defining:
(i) a plurality of input waveguides for receiving the input beams from the array of beam emitters and propagating the beams over the substrate,
(ii) focusing optics for receiving the beams from the input waveguides and converging the received beams toward a dispersive element,
(iii) a dispersive element for receiving the converged beams and dispersing the converged beams, thereby forming a dispersed beam, and
(iv) an output waveguide for receiving the dispersed beam from the dispersive element, an output facet of the output waveguide (a) comprising a portion of an exterior surface of the substrate, and (b) forming a partially reflective output coupler that (A) transmits a first portion of the dispersed beam as a multi-wavelength output beam and (B) reflects a second portion of the dispersed beam back toward the dispersive element and the array of beam emitters, thereby forming an external cavity that stabilizes each of the input beams at a different wavelength.
21. An apparatus for producing a multi-wavelength output beam from beams emitted by an array of beam emitters, the apparatus comprising a glass substrate, portions of the substrate defining:
(i) a plurality of input waveguides for receiving the input beams from the array of beam emitters and propagating the beams over the substrate, wherein at least portions of the input waveguides are mutually angled andor curved to overlap the input beams at a point proximate a dispersive element,
(ii) a dispersive element for receiving the overlapped beams and dispersing the overlapped beams, thereby forming a dispersed beam, and
(iii) an output waveguide for receiving the dispersed beam from the dispersive element, an output facet of the output waveguide (a) comprising a portion of an exterior surface of the substrate, and (b) forming a partially reflective output coupler that (A) transmits a first portion of the dispersed beam as a multi-wavelength output beam and (B) reflects a second portion of the dispersed beam back toward the dispersive element and the array of beam emitters, thereby forming an external cavity that stabilizes each of the input beams at a different wavelength.