CN101994959B - White light emitting apparatus in image reading device and linear illuminator using same - Google Patents
White light emitting apparatus in image reading device and linear illuminator using same Download PDFInfo
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- CN101994959B CN101994959B CN2010102545739A CN201010254573A CN101994959B CN 101994959 B CN101994959 B CN 101994959B CN 2010102545739 A CN2010102545739 A CN 2010102545739A CN 201010254573 A CN201010254573 A CN 201010254573A CN 101994959 B CN101994959 B CN 101994959B
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Abstract
The present provides a white light emitting apparatus in image reading device and linear illuminator using same, wherein a white LED emiting light devivating from an expected whiteness is combined; lights are emitted to the LED for colour mixrure, so that lights with the expected chromaticity is emitted. A white light emitting apparatus (20) includes a light source section in which a first white LED (11) that emits white light whose chromaticity deviates to a blue side from a predetermined white region of a CIE chromaticity diagram and a second white LED (12) that emits white light whose chromaticity deviates to a yellow side from the predetermined white region are adjacently disposed so as to emit light with optical axes in substantially the same direction, and a current regulator that independently drives the blue LED chip in the first and second white LEDs, respectively. A colour mixture of lights emitted from the first and second white LEDs (11, 12) is adjusted to a chromaticity of the predetermined white region using the current regulator.
Description
Technical field
The line-illuminating device that the present invention relates to the white light emitting device in the image read-out and use it.Particularly relate to the line-illuminating device that in image read-out, uses, carried the white light emitting device of White LED and used it.
Background technology
In the equipment such as facsimile machine, duplicator, manual scanning instrument, the image read-outs such as use imageing sensor are as the device that is used for reading original copy.Usually, as such image read-out, use light path short, be easy to contact image senser to the assembling of equipment.
Contact image senser possesses the line illuminator of wire ground irradiation master copy in the main scanning scope.As line illuminator, the line illuminator of known following indirect irradiation type: use long light conductor, the light of the light source incident from the end face that is configured in this light conductor is propagated in internal surface reflection, and from the wire exit facet outgoing of length direction.
Light source in known such line illuminator uses the White LED that is made of blue led chip and YAG class fluorophor.White LED light source reads corresponding to coloured image, compare with the multi-chip LED of the light that sends three kinds of colors of RGB, it is simple to light control, aspect light characteristic and miniaturization, lighting aspect can be described as goodly, be used as the light source of the contact image senser that luminous efficiency improves.
In addition, for the line-illuminating device of the LED that is consisted of by a plurality of light-emitting components in the configuration of the end face of light conductor as light source, illuminant colour abundant colour mixture in light conductor that requirement utilizes these a plurality of chips to obtain, in the situation of not breaking color balance, discharge, as the illumination of the homogeneous hue of wire and shine colored original.As being used for addressing these problems or in the characteristic invention of shape tool of light conductor, disclosing patent documentation 1 etc.
In addition, in patent documentation 2, disclose in the situation of batch production White LED, produced sizable deviation aspect the emission wavelength of blue led chip and the luminosity.In addition, owing to the amount of the fluorescent particles of sneaking into the YAG class fluorophor in the cladding parts or the deviation of dispersion etc., also can affect mixed white light, its result, the White LED of finishing produces larger deviation aspect hue and luminance.
Here, with reference to Figure 16, the distribution of the deviation of its luminous tone when producing certain White LED in batches is described with the part of chromaticity coordinate.In addition, distribution map shown in Figure 16 is disclosed in the patent documentation 2.Each stain shown in Figure 16 illustrates each tone data of White LED, and this tone is separated into as shown in the figure to top-right band shape.More particularly, be dispersed in based on the white portion on the substantial line colourity differentiation, that after blueness is passed through white point, pass through yellow of JIS Z 8110 bandedly.Here, the dispersion of width (arrow line A) mainly is the tone variation that the deviation owing to the emission wavelength of blue light emitting device produces, and the dispersion of length direction (arrow line B) mainly is the tone variation that the deviation owing to the amount of sneaking into the fluorescent particles in the cladding parts or dispersion produces.In addition because the emission wavelength of blue light emitting device batch between deviation large, so in the batch production of reality, the dispersion of width (arrow line A) further enlarges (with reference to patent documentation 2).
[patent documentation 1] TOHKEMY 2006-287923 communique
[patent documentation 2] TOHKEMY 2004-119743 communique
No. 3990437 communique of [patent documentation 3] Japan Patent
Summary of the invention
Here, come with such White LED in hope in the situation of light source of the line-illuminating device that the composing images reading device uses, only using in the situation that White LED that its illuminant colour additional level is selected consists of in the chromaticity range of expectation, is preferred at center tone, tone aspect unequal.But, in the situation of the structure of the White LED of the product that only uses specific additional level, exist the product of other grade useless, as the high problem of totle drilling cost that is used for obtaining White LED.
The present invention makes in view of above-mentioned existing problem, the line-illuminating device that a kind of white light emitting device is provided and uses it, wherein depart from and consist of with the luminous White LED of the whiteness of wide region by the whiteness of combination from expectation, its illuminant colour is carried out colour mixture and makes it send the light of expectation colourity.Its purpose is, the utilizability of the White LED of the colourity by further raising wide region improves the utilization rate of White LED, reduces the manufacturing cost of white light emitting device.
In the white light emitting device in image read-out involved in the present invention, use has the White LED of blue led chip and fluorophor, it is characterized in that, have: light source portion, make optical axis roughly in the same direction disposed adjacent the first White LED and the second White LED are arranged, wherein, described the first White LED sends the white light of being partial to the colourity of blue side from the regulation white area of XYZ chromaticity diagram, and described the second White LED sends the white light of being partial to the colourity of yellow side from described regulation white area; And current control unit, drive independently respectively the described blue led chip in described the first and second White LEDs, wherein, described current control unit carries out PWM control to the drive current of at least one party in described the first and second White LEDs, be inversely proportional to the distance of luminous chroma point from the target chroma point on the XYZ chromaticity diagram to described the first White LED and the distance of the luminous chroma point from described target chroma point to described the second White LED, set the pulse width separately that is used for driving described the first and second White LEDs, will be adjusted to from the luminous colour mixture of described the first and second White LEDs the colourity of described regulation white area thus.
In the white light emitting device in image read-out involved in the present invention, use has the White LED of blue led chip and fluorophor, it is characterized in that, have: light source portion, make optical axis roughly in the same direction disposed adjacent the first White LED and the second White LED are arranged, wherein, described the first White LED sends the white light of being partial to the colourity of blue side from the regulation white area of XYZ chromaticity diagram, and described the second White LED sends the white light of being partial to the colourity of yellow side from described regulation white area; And current control unit, drive independently respectively the described blue led chip in described the first and second White LEDs, wherein, described current control unit is in described the first and second White LEDs, send a White LED sustainable supply constant current of the white light of the colourity close to the target chroma point on the described XYZ chromaticity diagram, to the electric current after another White LED supply PWM control, the dutycycle of described PWM control set for and described XYZ chromaticity diagram on colourity and the colourity of the distance between the described target chroma point and described another White LED and the value that the distance between the described target chroma point is inversely proportional to of a described White LED, will be adjusted to from the luminous colour mixture of described the first and second White LEDs the colourity of described regulation white area.
Line-illuminating device involved in the present invention is characterised in that, make from the light of the light source incident internal surface reflection at bar-shaped light guide, it is penetrated from the exiting surface that arranges along its length, wherein, the plane of incidence on the end face of described surface of light source on the length direction that is arranged on the bar-shaped light guide that is made of transparent component and disposing, described light source is above-mentioned white light emitting device.
Line-illuminating device involved in the present invention is characterised in that, radiates the profile of emitting surface of the light of described white light emitting device, is the size of takeing in the profile of the plane of incidence of light conductor.
According to white light emitting device involved in the present invention, the White LED of the illuminant colour by the colourity that departs from from the regulation white area in the white area that the additional level that provides as product is provided can utilize the White LED of the colourity of wide region.That is, by before cutting down because the deviation of the intrinsic tone of the White LED that is consisted of by blue led chip and YAG class fluorophor and the quantity of useless product reduces the manufacturing cost of White LED.
In addition, according to white light emitting device involved in the present invention, need not numerous and diverse structure of adopting in order to compensate the prior aries such as composition of newly appending the led chip that sends different wave length or different types of fluorescent material or change fluorophor as the chromaticity distortion of the shortcoming of White LED, just can carry out luminous as the white area of the regulation of target.
In addition, for example by white light emitting device involved in the present invention being used as the light source of line-illuminating device, the bright line-illuminating device that the white colourity that can make economically to stipulate is thrown light on.
Description of drawings
Fig. 1 is the oblique view of light source portion that the white light emitting device of embodiments of the invention 1 is shown.
Fig. 2 is the figure of an example of circuit diagram that the driving white light emitting device of embodiments of the invention 1 is shown.
Fig. 3 is the figure for the control of the time of lighting of two White LEDs of explanation embodiments of the invention 1.
Fig. 4 utilizes the figure that typical white portion is described based on the chromaticity coordinate of JIS Z 8110.
Fig. 5 A illustrates that light-emitting zone with the White LED of a manufacturer is divided into 4 grades and the figure of the example that represents at XYZ chromaticity diagram.
Fig. 5 B is the figure that illustrates based on the coordinate figure at each regional angle of the grade classification of Fig. 5 A.
Fig. 6 A illustrates that light-emitting zone with the White LED of a manufacturer is divided into 7 grades and the figure of the example that represents at XYZ chromaticity diagram.
Fig. 6 B is the figure that illustrates based on the coordinate figure at each regional angle of the grade classification of Fig. 6 A.
Fig. 7 A illustrates the figure that the luminescent chromaticity in the commercially available prod of White LED again additional level is formed A, B, C district and represents at chromatic diagram.
Fig. 7 B illustrates the figure of coordinate figure at each angle in the A that has again added grade, B, the C district of Fig. 7 A.
Fig. 8 is explanation to the luminous chromatic diagram that carries out the control of colour mixture from two White LEDs of the white light emitting device of embodiment involved in the present invention 1.
Fig. 9 is for the figure of explanation as the white light emitting device of the first or second White LED of the light of the colourity of the banded regions in the outside of the white area of sending additional level.
Figure 10 is the figure be used to the luminous colourity of the white light emitting device that embodiment involved in the present invention 2 is described.
Figure 11 is the figure be used to the control of the time of lighting of two White LEDs that embodiment involved in the present invention 2 is described.
Figure 12 is the oblique view of structure that the line-illuminating device of embodiment involved in the present invention 3 is shown.
Figure 13 is the figure of the emitting surface of the white light emitting device that uses at the light source of the line-illuminating device of embodiment involved in the present invention 3 for explanation.
Figure 14 is the figure in cross section of CIS unit that has assembled the line-illuminating device of embodiment involved in the present invention 3 for explanation.
Figure 15 is the figure of the Illumination Distribution on the length direction that obtains for explanation becomes RGB with the illumination light light splitting of the line-illuminating device of embodiment involved in the present invention 3.
Figure 16 is the distribution map that the chromaticity distortion of White LED is shown.
Description of reference numerals
10: the light source portion of white light emitting device
11: the first white-light luminescent components
12: the second white-light luminescent components
13: the blue led chip
20: white light emitting device
33: current control division
50: line-illuminating device
51: light conductor
54: the plane of incidence
55: lens arra
56: line sensor
The 57:CIS printed base plate
58: clear glass original copy brace table processed
59: the paper original copy
60: contact image senser unit, CIS unit
63: emitting surface
65: the white area of additional level
66: banded regions
67: typical white area
The specific embodiment
The present inventor has studied the characteristic of the White LED with blue led chip and fluorescent material, and studied with uniform whiteness and sent the white light emitting device of the high light of exporting and white luminous lighting device, finished the present invention by being easy to structure.
In addition, white as the lighting source in the present embodiment, be typically with reference to the accompanying drawings 1 " the general colourity of system's color name is distinguished " that in the JIS standard, is defined as shown in Figure 4 JIS Z 8110, wherein be divide into white, (indigo plant) white, (purple) is white, (Huang) is white, (green) is white, the color of (shallow) powder, is called in the present invention typical " white ".
Be called white balance with adjusting the mixing ratio of light and being adjusted to so that the color of lighting source becomes target white.This adjustment is carried out with the measuring transducer instrument, but in the present embodiment, uses spectrophotometer, the xy coordinate on lightness, brightness, colourity and the XYZ chromaticity diagram of mensuration or calculating White LED etc.But, even adjust white balance with the measuring transducer instrument beyond the spectrophotometer, also fully no problem when enforcement is of the present invention.
In each company of the manufacturer of White LED is included in the white point on the XYZ chromaticity diagram (x=0.33, y=0.33), with the zone of the one fixed width in the above-mentioned typical white portion and length as the light-emitting zone of White LED and additional level provides.For example, in the catalogue (2008 annual version) of Nichia Chemical Industries, Ltd's (being designated hereinafter simply as N company), shown in Fig. 5 A, be classified as a0, b1, these 4 zones of b2, c0.Coordinate figure at each regional angle shown in Fig. 5 B.In addition, in the catalogue (version in 2008) of the blue led of Toyoda Gosei Co., Ltd.'s (being designated hereinafter simply as T company)+fluorescence build White LED, light-emitting zone as shown in Figure 6A is classified as AA, AB, these 7 zones of B3～B6, C0.The coordinate figure at each regional angle shown in Fig. 6 B.The overall area that has added grade of two companies is identical and overlap on XYZ chromaticity diagram, and is only different on the regional rank of segmentation.
Here, for present embodiment is described, with the zone of these additional level additional level and become A, B, these 3 zones of C again.Namely, the a0 zone of N company is same area (hereinafter referred to as the A district) with (AA+BB) zone of T company, the c0 zone of N company is same area (hereinafter referred to as the C district) with the C0 zone of T company, (b1+b2) zone of N company is same area (hereinafter referred to as the B district) with (B3+B4+B5+B6) zone of T company, is the zone that overlaps respectively.Again added like this light-emitting zone of grade shown in Fig. 7 A.A district shown in Fig. 7 A, B district and C district are the zones to the luminescent chromaticity additional level in the White LED commercially available prod.In addition, the coordinate figure at the angle in each district shown in Fig. 7 B.In Fig. 7 A, there is white point (x=0.33, y=0.33) on the border in B district and C district, shown in Fig. 7 A, the B district is near blue zone from white point.
Below will be somebody's turn to do (A+B+C) and distinguish the white area that is called additional level.In addition, the B district is called regulation white area (tone of expectation), is the target tone of the illuminant colour of the white light emitting device among the embodiment.Like this, manufacturer is the white area of the white luminous additional level of having added grade and having obtained of White LED, is that regulation white area (B district) is positioned at its central authorities, is partial to blue side from this regulation white area and connects zone on the XYZ chromaticity diagram in A district, the yellow side connection of deflection C district.In addition, shown in Fig. 7 B, the coordinate figure (x on the XYZ chromaticity diagram, y) regulation white area (B district) is by (0.296,0.276), (0.283,0.305), (0.330,0.360), the colourity in the scope of (0.330,0.318) these 4 encirclements.In addition, the A district is by (0.280,0.248), (0.264,0.267), (0.283,0.305), (0.296,0.276) colourity in the scope of these 4 encirclements, the C district is by (0.330,0.318), (0.330,0.360), (0.361,0.385), the colourity in the scope of (0.356,0.351) these 4 encirclements.
In addition, in the image read-out that has used white light emitting device involved in the present invention or line-illuminating device, not that light source or its reverberation are wanted the object of Direct Recognition as human eye, but the mechanism that is received and identified by photoelectric conversion sensor.Therefore, the center tone of illuminant colour needn't be the white point (x=0.33, y=0.33) on the XYZ chromaticity diagram, but the economy of considering the light source cost in the adjustable range of image read-out is come the tone of selected light.
In addition, as the central coordinate in B district, adopt the coordinate figure (x=0.307, y=0.315) at total angle, the B3 shown in Fig. 6 A～B6 zone, the coordinates of targets value (target chroma point) that should reach as the colourity in the present embodiment.Therefore, as the light source in the image read-out of object of the present invention, if only consist of with the White LED in B district, be preferred suppressing easily the uneven this point of tone then, but A district and C zone are useless, therefore see it is the problem that should consider from the viewpoint of cost.
The invention provides a kind of white light emitting device or line-illuminating device, in the White LED of the light of the colourity of the white area of sending additional level that manufacturer provides, use will be from the A district that departs from of regulation white area (B district) or the C district as the White LED of illuminant colour, the tone of adjustment illuminant colour is luminous.As a result, cut down the quantity of useless White LED.The concrete example of invention below is described.
[embodiment 1]
Two White LEDs are set in the white light emitting device that uses in the image read-out of embodiment 1.The radiating light excitation that in any one White LED, also comprises the blue led chip and sent by this blue led chip and send the luminescent coating of sodium yellow.Yellow is blue complementary color.Here, with reference to Fig. 1～Fig. 4 and Fig. 9, the white light emitting device 20 that is provided with two White LEDs is described.
The white light emitting device 20 of present embodiment comprises light source portion 10 and current control division 33 and consists of.Fig. 1 illustrates the light source portion 10 of white light emitting device 20.On this light source portion 10, send the blue side of regulation white area (B district) deflection the white area (A district+B district+C district) from above-mentioned additional level A district white light the first White LED 11 and send second White LED 12 of white light of being partial to the C district of yellow side from regulation white area (B district) and be adjacent to be installed on the printed base plate 15.In addition, the first and second White LEDs 11,12 with its main light emission direction, be that optical axis is parallel to each other and becomes roughly unidirectional mode disposed adjacent.On printed base plate 15, as the wiring 16 that is used for feed, two White LEDs 11,12 anode lines and two cathode line that are connected with each White LED 11,12 that have are set.These anode lines with are connected a cathode line respectively from terminal A, K1, K2 and be arranged on outside current control division 33 (with reference to Fig. 2) and be connected.By this current control division 33, drive independently respectively first and second White LEDs 11,12 of the light source portion 10 that consists of white light emitting device 20.In addition, diagram has been omitted the luminescent coating that covers the blue led chip in Fig. 1.
As the White LED that uses in this embodiment, for example size is about the commercially available surface mounting LED encapsulation of 2.0 * 1.2mm (Nichia Chemical Industries, Ltd makes in length and breadth; NESW007A), appointment obtains the White LED that illuminant colour is adjusted to A district and C district.Perhaps, can obtain the White LED of above-mentioned model, utilize above-mentioned measuring transducer instrument, the White LED of therefrom obtaining the light that sends the A district under the illuminating state with specified forward current 10mA uses with the White LED that sends the light in C district.
White light emitting device involved in the present invention will carry out colour mixture to the white light of two kinds of White LEDs and obtain the colourity in B district, comes this relation is described with reference to XYZ chromaticity diagram shown in Figure 8.In addition, the coordinate figure at the angle in each district is identical with Fig. 7 B.Here, the first White LED constitutes the white light LA1 of the chroma point PA1 in the A district that sends on the XYZ chromaticity diagram shown in Figure 8, and the second White LED constitutes the white light LC1 of the chroma point PC1 that sends C district shown in Figure 8.
Consistent with some PD0 shown in Figure 8 in order to make based on the colour mixture of the illuminant colour of the first and second White LEDs, lightness with the white light LC1 of the lightness of the white light LA1 of a PA1 and some PC1 is weighted, adjust lightness, so that the value that obtains after being weighted on average by the chromaticity coordinate to a PA1 with the chromaticity coordinate of putting PC1 becomes the chromaticity coordinate of regulation.In addition, some PD1 is the impact point that colour mixture should reach, and coordinate figure is (x=0.307, y=0.315), is the coordinate of the central authorities in above-mentioned B district.
The adjustment of the lightness of the illuminant colour of the White LED of present embodiment (bright degree) utilizes PWM control to carry out, and this PWM control is few and recommended owing to tone variations, and makes the forward current that drives each led chip constant, the change pulse width.
Next, the method for adjustment of the colour mixture in the white light emitting device 20 of present embodiment is described.Fig. 2 is the figure that illustrates for an example of the circuit that drives white light emitting device 20.Comprise light source portion 10 in this circuit and as the current control division 33 of current control unit.Light source portion 10 is equivalent to part shown in Figure 1.In current control division 33, be provided with independently respectively for the current control division that is controlled at the first and second White LEDs 11,12 electric currents that flow.For example, the first and second White LEDs 11,12 each in the middle of, the upper matrix current adjustment circuit 21,22 that is connected with of two cathode terminal K1, K2 of light source portion 10 parallel with one anotherly.In addition, be used for each White LED 11 of on/off, 12 transistor T 1, T2 are connected with matrix current adjustment circuit 21,22 respectively.Transistor T 1, T2 are connected with ground connection GND.
In matrix current adjustment circuit 21,22, be provided with for example operational amplifier, transistor and current-limiting resistance R1 or current-limiting resistance R2.By current control division 33, the forward current of the regulation that flows respectively in White LED 11,12 utilizes the PWM control mode, makes respectively transistor T 1, T2 on/off, thus control White LED 11,12 light.Such current control division 33 works as current control unit.
Next the white light emitting device 20 that is used for making present embodiment having been carried out the Current Control that the illuminant colour after the colour mixture reaches the actual impact point that should reach on chromatic diagram describes.Fig. 3 is the sequential chart that the first and second White LEDs 11, time of lighting of 12 is carried out PWM control.
At first, the cycle T of pulse is made as 10 milliseconds, utilize matrix current adjustment circuit 21,22 will drive the first and second White LEDs 11,12 electric current is made as specified 10mA, and the time of the lighting t1 of the first White LED 11 is made as 5 milliseconds of each cycles, makes white light emitting device 20 actions.In addition, utilize respectively matrix current adjustment circuit 21,22 to set White LEDs 11,12 drive current, utilize transistor T 1 to adjust and light time t1.
Next, above the light-emitting area of white light emitting device 20, leave the position from two White LEDs 11,12 luminous well-mixed distance, perhaps having placed above its of scatter plate, the measuring transducer instrument is set, the colour measurement of the illuminant colour of beginning white light emitting device 20.Here, the time more than tens times with cycle T begins colour measurement as Measuring Time.
Then, utilize transistor T 2 adjust White LEDs 12 each cycle light time T 2, find out the basically identical time of the lighting t2 of some PD0 (x=0.307, y=0.315) of the central authorities in the luminous colour measurement value of white light emitting device 20 and B district shown in Figure 8.
Here, in order to make the colourity of having carried out the illuminant colour after the colour mixture by white light emitting device 20 basically identical with the some PD0 as the coordinate figure of the substantial middle in the B district of target on XYZ chromaticity diagram, the PWM control that utilization is undertaken by current control division 33, with dutycycle D1=t1/T the first White LED 11 is lighted, and with dutycycle D2=t2/T the second White LED 12 is lighted to get final product.
In addition, depend in A district corresponding to illuminant colour selected and the first White LED coordinate position or with C district corresponding to the illuminant colour of the second White LED in coordinate position, existence can not make its colour mixture and the consistent situation of some PD0.But, because can be consistent with the colourity in the B district, therefore can fully satisfy the needs that solve technical problem of the present invention.In addition, because the white area of all additional level is with arc connection A district+B district+C district, so in the situation of the White LED of the light of the colourity of having selected to send the arc extreme inboard in A district and the C district, the chromaticity coordinate of colour mixture very likely departs from a little from the B district.In this case, as long as judge whether the colourity of this colour mixture can allow.
Suppress the existing white light emitting device of irregular colour with respect to the White LED of the light of only selecting to send narrow regulation white area, the White LED of the illuminant colour of the colourity that the regulation white area from the white area of the additional level that provides as product departs from also is provided white light emitting device involved in the present invention.Therefore, according to the present invention, can select in the past the quantity of no White LED owing to the deviation of the intrinsic tone of the White LED that is consisted of by blue led chip and YAG class fluorophor by reduction, thereby can reduce the cost of product.
In addition, according to the present invention, can make following white light emitting device: need not numerous and diverse structure of adopting in order to compensate the prior aries such as composition of newly appending the led chip that sends different wave length or different types of fluorescent material or change fluorophor as the chromaticity distortion of the shortcoming of White LED, just can carry out luminous as the regulation white area of target.
In addition, as the Current Control in the white light emitting device 20, can drive the control of the size of White LED 11,12 electric current, replace the control of PWM mode.The control of size of current can be undertaken by matrix current adjustment circuit 21,22.In addition, also can make up the control of PWM mode and the control of size of current.
In addition, in the above-described embodiments, the white area of the additional level that provides based on manufacturer has illustrated the luminous colourity of White LED.But, the distribution of the luminous colourity of the White LED that is consisted of by blue led chip and YAG class fluorophor, the white area between the yellow region of the blue-light-emitting district that obtains the blue led chip and light-emitting phosphor that also can in banded regions shown in Figure 9 66, distribute on the XYZ chromaticity diagram.The previously defined with reference to the accompanying drawings typical white area 67 of 1 (with reference to Fig. 9) based on JIS Z 8110 standards, be the white area (A district+B district+C district) 65 that expands to additional level the outside and will be on XYZ chromaticity diagram from the point (x=0.23, y=0.21) of the close blue side of white point near the point (x=0.41, y=0.41) of yellow side roughly as the elliptoid zone of major axis.The present invention also can be distributed in for the illuminant colour of White LED the White LED of the banded regions 66 of the colourity in this typical case's white area 67.
Be partial to the White LED of white light of colourity of blue side as the first White LED with being emitted in the banded regions 66 in the outside of white area of this additional level from expectation white area (B district), similarly, the White LED of white light that is emitted in the colourity of being partial to yellow side in the banded regions 66 in the outside of white area of this additional level from expectation colourity district (B district) as the second White LED, is equally correspondingly made white light emitting device with above-described embodiment.And, more to be partial to than the A district in the situation of colourity of white area of blue side at the illuminant colour of the first White LED, more to be partial to than the C district in the situation of colourity of white area of yellow side at the illuminant colour of the second White LED perhaps, PWM control that also can be by current control division 33 similarly makes its luminescent chromaticity consistent with colourity in the B district as white light emitting device 20.
Like this, widely selected in the wide region in banded regions 66 in the situation of the luminous colourity of the first or second White LED, from the target colourity of the luminous colour mixture of two White LEDs or regulation white area needn't certain limitation in the B district, as long as the central area between the luminous chroma point of two White LEDs, the chroma point of this colour mixture also can move to blue side or the yellow side in B district.
Like this, the colourity of the wide region in the white area outside by can selecting additional level can further increase the utilizability of White LED, and can reduce product cost as the illuminant colour of the first or second White LED.
[embodiment 2]
At first illustrate on XYZ chromaticity diagram, in the situation that the distance of the impact point PD0 of the coordinate points of two White LEDs 11 that will use, 12 the luminous colourity separately colourity after the colour mixture there are differences, adjust the Current Control of the colourity of the white light emitting device that is consisted of by these two White LEDs.At this moment, preferably select the roughly the same White LED of luminous luminosity under the rated current of the first White LED 11 and the second White LED 12.In order to make luminosity consistent, can specify the luminosity grade and obtain from manufacturer, perhaps drive separately to measure luminosity and select.
For example, shown in the XYZ chromaticity diagram of Figure 10, the colourity LA2 of the illuminant colour of the first White LED 11 is positioned at the PA2 in A district, and the colourity of the illuminant colour LC2 of the second White LED 12 is positioned at the PC2 in C district.Below explanation is adjusted to the right place it on the line segment that connects these two some PA2, PC2 and is positioned at the situation of tone of some PD0 of the substantial middle in B district.For this reason, can adjust the lightness of illuminant colour separately, so that the weighted average of the lightness of utilizing its illuminant colour LA2, LC2 after the coordinate of PA2, PC2 is weighted becomes the coordinate figure of PD0.In the situation of present embodiment, as shown in figure 10, because between the distance (PA2-PD0) and the ratio of distances constant of distance between (PC2-PD0) be 1 to 2, so by the ratio with illuminant colour LA2 and the lightness of LC2 be adjusted into ratio of distances constant be inversely proportional to 2 to 1, just make the colourity that roughly becomes a PD0 from the illuminant colour of the colour mixture of white light emitting device.
Above-mentioned explanation be the situation that the colourity PC2 of the target chroma point PD0 of colourity PA2, colour mixture of as shown in figure 10 the first White LED and the second White LED roughly is located along the same line on XYZ chromaticity diagram.But, even they are not located along the same line, as long as with between the distance (PA2-PD0) and set inversely the lightness of illuminant colour LA2 and LC2 apart from the distance between (PC2-PD0), the colour mixture of both illuminant colours just roughly becomes the colourity in regulation white area (B district), but suitable.
If express in addition the method for adjustment of this colour mixture, then be to make lightness with the luminous White LED of the colourity close to the impact point PD0 of the colourity after colour mixture be higher than lightness with another luminous White LED of the colourity of the position away from impact point PD0.In the white light emitting device of the present embodiment of these two White LEDs having been selected the roughly the same White LED of luminosity, use current control division 33, matrix current adjustment circuit 21 by Fig. 2, sustainable supply constant current (not being pulse current) is as the drive current from the White LED 11 of impact point PD0 close to more.Under this state, only supply with the drive current of another White LED 12 by PWM control, determine its pulse width t2 according to similarly to Example 1 method, so that the colour mixture of two White LEDs consistent with target colourity (with reference to Figure 11).
Except this Current Control shown in Figure 11, utilize current control division 33 with cycle T be made as 100 milliseconds, with t1 (having carried out pulse width after the PWM control with the drive current of White LED 11) be made as 90 milliseconds, when t2 is made as 45 milliseconds, colour mixture is roughly target colourity, but confirms that its lightness is high in the situation of the Current Control of Figure 11.Certainly, the setting that half that make t1 identically with the cycle come Continuous Drive White LED 11, t2 is set as t1 drives White LED 12 also is suitable.
If the pulse width establishing method in the above PWM control is summarized, then for the first and second White LEDs the two, use the measuring transducer instrument to measure in advance each self luminous colourity, calculate the distance separately at the target chroma point PD0 after the colour mixture on the XYZ chromaticity diagram.This drive current apart from a short White LED is supplied with constant current.Perhaps, undertaken in the situation of electric current supply by PWM control, be set as so that the dutycycle of its pulse width P is very big.On the other hand, it is suitable that the pulse width p that be used for to drive one White LED of this distance is set as the value that is inversely proportional to this distance with respect to pulse width P.Certainly, also can as embodiment 1, adjust the pulse width of a White LED of the distance that is driven into the target chroma point when utilizing the measuring transducer instrument that colour mixture is monitored.
In the present embodiment, the ratio (t1/t2) of the pulse width t1 of the White LED 11 close to the PD0 and the pulse width t2 of White LED 12 away from a PD0 since t1 greatly can set largelyr.This can make distance (PC2-PD0) elongated with respect to distance (PA2-PD0), can utilize the White LED that sends from the light of the farther colourity of colour mixture impact point PD0.This can improve the utilizability of the White LED of the light that sends the colourity that departs from from regulation white area (B district), the totle drilling cost when reduction obtains White LED.
[embodiment 3]
Embodiment 3 relates to the line-illuminating device 50 of the white light emitting device 20 that has used embodiment 1.With reference to Figure 12～Figure 15 this line-illuminating device 50 is elaborated.
The line-illuminating device 50 of present embodiment is used for the master copies such as paper of illumination image reading device.In this line-illuminating device 50, as shown in figure 12, be provided with the bar-shaped light conductor 51 that consisted of by transparent material and towards the light source portion 10 of the plane of incidence 54 configurations of an end that is arranged on this light conductor 51.Light source portion 10 is connecting current control division 33 (not shown in Figure 12) via terminal wire 62 as embodiment 1.And, be provided with at light conductor 51: light guide section 52, inner surface reflection and while at light conductor 51 guide in the longitudinal direction from the light of the plane of incidence 54 incidents, and light out part 53, have be used to the exiting surface that makes from the light wire ejaculation along its length of light guide section 52.
In addition, as shown in figure 13, the appearance and size of emitting surface 63 of the light of radiation light source portion 10 is designed to abundantly to take in the profile of the plane of incidence 54 of light conductor 51, thereby so that from the light of light source portion 10 can be not lavishly from the plane of incidence 54 incidents of light conductor 51.For example, in face one side of light of radiation light source portion 10, arrange as shown in figure 13 two each be of a size of the White LED of 1.2mm * 2mm, the appearance and size of face one side of the light of radiation light source portion 10 is 2.5mm (laterally) * 2mm (vertically).On the other hand, the appearance and size of the plane of incidence 54 of light conductor 51 shown in Figure 12 forms 3.5mm (W direction) * 2.5mm (H direction).In addition, be to dispose by the plane of incidence 54 that the emitting surface 63 with light source portion 10 is positioned as close to light conductor 51, and make the design of not inciding lavishly light conductor 51 from the light of white light emitting device 20.
In addition, as light conductor 51, for example can use and the corresponding light conductor that is used for the three primary colors color light source with the LED alignment arrangements (allocation position is different) of 3 kinds of wavelength (for example red, green, blue).Namely, can use the light conductor that is designed for the wire illumination, in this light conductor, make light from plane of incidence incident from the different a plurality of light sources of wavelength, carry out suitable reflection and scattering for each wavelength in light conductor, the output of each wavelength distributes and outgoing along its length equably.Details with light conductor of such function for example is disclosed in the patent documentation 1.
Therefore, even between two White LEDs 11,12 as the light source portion 10 of the white light emitting device 20 of light source, there is the tone difference of illuminant colour, and two centre of luminescence points are not in the situation of same position, even and from white light emitting device 20 to the plane of incidence 54 distance short, can not realize between them in the situation of sufficient colour mixture that light conductor 51 also can be with from the incident light of the plane of incidence 54 colour mixture and penetrate the line illumination light that even whiteness distributes fully.
The present inventor has confirmed the above-mentioned effect of the line-illuminating device 50 of present embodiment according to following process.At first, as shown in figure 14, line-illuminating device 50 is assembled in the contact image senser unit (being designated hereinafter simply as the CIS unit) 60 of composing images reading device.In addition, although do not illustrate, the current control division 33 of white light emitting device 20 connects via connector 61.
In this CIS unit 60, utilize lens arra 55 to make from imaging on the reverberation on-line sensor 56 of paper original copy 59.As line sensor 56, the line sensor (omitting diagram) that uses the pixel columns of 3 row of the straight line that carries out opto-electronic conversion by being used for receiving red (R), green (G), blue (B) light of all kinds to consist of.In this line sensor 56, have 3 kinds of colour filters in the transmission peak wavelength zone corresponding with RGB in each pixel column configuration.Therefore, each pixel column is respectively to work corresponding to RGB spectral sensitivity of all kinds.Such sensor array is documented in such as in patent documentation 3 grades.
Therefore, this CIS unit 60 will become RGB of all kinds from the reverberation light splitting of the white of paper original copy 59, can measure illumination for each pixel of arranging at the length direction of pixel column.The illumination photometry value representation of this each pixel be with from as the plane of incidence side of an end face on the length direction on the light conductor 51 to Illumination Distribution corresponding to another end face.
Next, with paper original copy 59 replace with specified standard with white paper after, utilize similarly to Example 1 current control division 33 drive the first and second White LEDs 11,12 the two.Then measure RGB relative illumination of all kinds for the illumination light of line-illuminating device 50, as the Illumination Distribution of line direction.At this moment, the electric current that flows in two White LEDs 11,12 is set as respectively 10mA.In the measurement result of this Illumination Distribution, as shown in figure 15, red with green relative illumination is almost identical value, and being distributed as substantially uniformly in the longitudinal direction distributes.In addition, blue being distributed as and substantially distributing uniformly in the longitudinal direction demonstrates than red and green high relative illumination.
The illuminant colour of the white light emitting device 20 that uses in the line-illuminating device 50 of embodiment 3 is the light source of colourity that is adjusted to the B district of Fig. 7 A in embodiment 1, and the relative illumination of blueness is slightly large.But the size difference of the relative illumination of red, green, blue can utilize the data processing division in the image read-out of controlling the CIS unit to adjust.By being taken into light conductor 51 and the advantage of the line-illuminating device that wire ground throws light on to paper is from the white light emitting device 20 of embodiment 1 luminous, in light conductor 51, from the different illuminant colour of the tone of two White LEDs by abundant colour mixture.The shortcoming of the White LED that is made of blue led chip and YAG class fluorophor is, and is yellow strong etc. at luminous light beam periphery, has irregular colour at central authorities and the periphery of light beam.After will the abundant scattering of each illuminant colour and colour mixture from the first and second White LEDs in light conductor 51, light beam with wire throws light on to master copy, and the input after being received its reverberation and carried out opto-electronic conversion by line sensor 56 via lens arra 55 as shown in figure 15.Can confirm as shown in figure 15, although in RGB relative illumination of all kinds, there are differences (blueness is larger), but along the main scanning direction (from plane of incidence side to the opposing face side) of the CIS unit colour mixture of all carrying out equably of all kinds, become the relative illumination of substantially constant homogeneous from the reverberation of original copy.Therefore, the line-illuminating device of present embodiment is the invention of characteristic that effectively utilizes the white light emitting device 20 of embodiment 1.In addition, the line-illuminating device that uses the white light emitting device of embodiment 2 also can obtain having same effect.
White light emitting device involved in the present invention and line-illuminating device are used effectively and process colored image read-out in image reading apparatus, facsimile machine or duplicator etc.
Claims (6)
1. a white light emitting device is the white light emitting device in the image read-out, uses the White LED with blue led chip and fluorophor, it is characterized in that having:
Light source portion, make optical axis roughly in the same direction disposed adjacent the first White LED and the second White LED are arranged, wherein, described the first White LED sends has the white light of chroma point of being partial to the chromaticity coordinate value of blue side from the regulation white area of XYZ chromaticity diagram, and described the second White LED sends has the white light of chroma point of being partial to the chromaticity coordinate value of yellow side from described regulation white area; With
Current control unit drives respectively the described blue led chip in described the first and second White LEDs independently,
Wherein, described current control unit carries out PWM control to the drive current of at least one party in described the first and second White LEDs, be inversely proportional to distance and the distance from described target chroma point to the luminous chroma point of described the second White LED from the target chroma point on the XYZ chromaticity diagram to the luminous chroma point of described the first White LED, set the pulse width separately at least one party who drives described the first and second White LEDs
To be adjusted to from the luminous colour mixture of described the first and second White LEDs the colourity of described regulation white area thus.
2. a white light emitting device is the white light emitting device in the image read-out, uses the White LED with blue led chip and fluorophor, it is characterized in that having:
Light source portion, make optical axis roughly in the same direction disposed adjacent the first White LED and the second White LED are arranged, wherein, described the first White LED sends has the white light of chroma point of being partial to the chromaticity coordinate value of blue side from the regulation white area of XYZ chromaticity diagram, and described the second White LED sends has the white light of chroma point of being partial to the chromaticity coordinate value of yellow side from described regulation white area; With
Current control unit drives respectively the described blue led chip in described the first and second White LEDs independently,
Wherein, described current control unit is to a White LED sustainable supply constant current in described the first and second White LEDs, that send the white of the colourity close to the target chroma point on the described XYZ chromaticity diagram, another White LED is supplied with the electric current that has carried out after the PWM control
The dutycycle of described PWM control set for and described XYZ chromaticity diagram on colourity and the colourity of the distance between the described target chroma point and described another White LED and the value that the distance between the described target chroma point is inversely proportional to of a described White LED,
To be adjusted to from the luminous colour mixture of described the first and second White LEDs the colourity of described regulation white area thus.
3. a line-illuminating device is characterized in that,
Make from the light of the light source incident internal surface reflection at bar-shaped light guide, it is penetrated from the exiting surface that arranges along its length, wherein, the plane of incidence on the end face of described surface of light source on the length direction that is arranged on the bar-shaped light guide that is made of transparent component and disposing, described light source is white light emitting device claimed in claim 1.
4. a line-illuminating device is characterized in that,
Make from the light of the light source incident internal surface reflection at bar-shaped light guide, it is penetrated from the exiting surface that arranges along its length, wherein, the plane of incidence on the end face of described surface of light source on the length direction that is arranged on the bar-shaped light guide that is made of transparent component and disposing, described light source is white light emitting device claimed in claim 2.
5. line-illuminating device as claimed in claim 3 is characterized in that,
The profile of emitting surface of radiating the light of described white light emitting device is the size of takeing in the profile of the plane of incidence of light conductor.
6. line-illuminating device as claimed in claim 4 is characterized in that,
The profile of emitting surface of radiating the light of described white light emitting device is the size of takeing in the profile of the plane of incidence of light conductor.
Applications Claiming Priority (4)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP2009186880A JP4474491B1 (en) | 2009-08-11 | 2009-08-11 | White light emitting device and line illumination device using the same |
| JP2009-186880 | 2009-08-11 | ||
| JP2010-049662 | 2010-03-05 | ||
| JP2010049662A JP4511634B1 (en) | 2010-03-05 | 2010-03-05 | White light emitting device in image reading device and line illumination device using the same |
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| CN101994959A CN101994959A (en) | 2011-03-30 |
| CN101994959B true CN101994959B (en) | 2013-02-27 |
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| EP2523534B1 (en) * | 2011-05-12 | 2019-08-07 | Ledengin, Inc. | Apparatus and methods for tuning of emitter with multiple LEDs to a single color bin |
| CN102853283A (en) * | 2011-06-30 | 2013-01-02 | 展晶科技(深圳)有限公司 | Light emitting diode lighting device |
| KR101941450B1 (en) * | 2012-08-02 | 2019-01-23 | 엘지디스플레이 주식회사 | Light emitting diode package |
| CN103234149B (en) | 2013-03-29 | 2015-07-15 | 京东方科技集团股份有限公司 | Backlight module, liquid crystal display and backlight drive control method |
| US10854800B2 (en) | 2014-08-07 | 2020-12-01 | Epistar Corporation | Light emitting device, light emitting module, and illuminating apparatus |
| KR20180077781A (en) * | 2016-12-29 | 2018-07-09 | 에이치피프린팅코리아 주식회사 | Image scanning apparatus and method for scanning thereof |
| JP7282767B2 (en) * | 2018-06-21 | 2023-05-29 | ヌヴォトンテクノロジージャパン株式会社 | white light emitting device |
Citations (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN1831423A (en) * | 2005-03-10 | 2006-09-13 | 佳能组件股份有限公司 | Linear lighting device and image access device using thereof |
| WO2008108468A1 (en) * | 2007-03-08 | 2008-09-12 | Rohm Co., Ltd. | Led illumination device and its drive method |
| CN101435557A (en) * | 2007-11-14 | 2009-05-20 | 索尼株式会社 | Plane light source apparatus and liquid crystal display apparatus |
Family Cites Families (6)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JP2002324685A (en) * | 2001-04-25 | 2002-11-08 | Sony Corp | Lighting device |
| JP4201167B2 (en) * | 2002-09-26 | 2008-12-24 | シチズン電子株式会社 | Manufacturing method of white light emitting device |
| JP3990437B2 (en) * | 2004-03-16 | 2007-10-10 | キヤノン・コンポーネンツ株式会社 | Color image sensor unit, image reading apparatus using the sensor unit, and control method thereof |
| JP4037888B2 (en) * | 2005-03-10 | 2008-01-23 | キヤノン・コンポーネンツ株式会社 | Line-shaped illumination device and image reading device using the same |
| US7926300B2 (en) * | 2005-11-18 | 2011-04-19 | Cree, Inc. | Adaptive adjustment of light output of solid state lighting panels |
| US8456388B2 (en) * | 2007-02-14 | 2013-06-04 | Cree, Inc. | Systems and methods for split processor control in a solid state lighting panel |
-
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|---|---|---|---|---|
| CN1831423A (en) * | 2005-03-10 | 2006-09-13 | 佳能组件股份有限公司 | Linear lighting device and image access device using thereof |
| WO2008108468A1 (en) * | 2007-03-08 | 2008-09-12 | Rohm Co., Ltd. | Led illumination device and its drive method |
| CN101435557A (en) * | 2007-11-14 | 2009-05-20 | 索尼株式会社 | Plane light source apparatus and liquid crystal display apparatus |
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