JP2012253815A - Image reading line light source and light guide unit - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an image reading line light source with light emission intensity, by which uniformity of lighting can be obtained in a longitudinal direction and conversion efficiency of fluorescent light is improved, and to provide a light guide unit.SOLUTION: The image reading line light source includes: an LED light source 1 generating blue light; a rod-like light guide body 3 in which the LED light source 1 is arranged at the end thereof and which transmits the blue light which is made incident on an inner part by reflecting it along a long-axis direction; a reflector 6 which surrounds the light guide body 3 by leaving a prescribed space with the light guide body 3 and in which an opening part constituted of a long groove is arranged along the long axis direction; and a phosphor layer 5 which is installed on a light guide body 3 side of the reflector 6 and emits excited fluorescence by absorbing the blue light.

Description

The present invention is formed on a reading object by irradiating the reading object (irradiated object) with light and reading transmitted light and reflected light from the reading object with a photosensor arranged in a line shape. The present invention relates to an image reading line light source used in an image reading device such as a copying machine or a scanner that converts images, characters, patterns and the like into electronic information.

In devices such as copiers and scanners used to digitize information such as images, characters, and patterns printed on paper media, the object to be read is illuminated with a linear light source such as a xenon (Xe) lamp. There are many things to do. For example, in paragraph [0020] of Japanese Patent Application Laid-Open No. 2002-190919 (see Patent Document 1), a xenon gas in which a phosphor film is formed by leaving phosphor non-applied portions (band-shaped light projection portions) 13a and 13b is used as a discharge medium. Aperture-type fluorescent lamps 12a and 12b are disclosed.

In addition, light sources using LEDs that emit blue light or ultraviolet light instead of Xe lamps are widely used as linear light sources. For example, in paragraph [0023] of Japanese Patent Laid-Open No. 2000-127505 (see Patent Document 2), the fluorescent strips 30 and 32 and the non-fluorescent strip 34 are made of glass or plastic material in response to the blue light 36 emitted from the LED 26. A light source assembly 18 is disclosed that generates composite “white” light 38 from a constructed transparent rod lens 28.

In paragraph [0014] of Japanese Patent Application Laid-Open No. 2004-85824 (see Patent Document 3), there is a transparent plate (glass plate or the like) 12 in which a phosphor 13 in which several types of luminescent colors are blended is applied above an LED 11 that emits ultraviolet light. There is disclosed a long light source (linear light source) 10 that is arranged and emits visible light when ultraviolet light UV emitted from an LED 11 strikes a phosphor 13.

In paragraph [0015] of Japanese Patent Laid-Open No. 10-79835 (see Patent Document 4), visible light 6 converted from ultraviolet rays 4 by a phosphor 5 applied to the inner surface of the tube of the light source 1 and the opening of the light source 1 are disclosed. An illumination device is disclosed that irradiates a document 7 with synthetic visible light composed of visible light 6a obtained by converting ultraviolet rays 4a directly radiated from the unit 2 by a fluorescent member 9 composed of a phosphor 10 and a reflective film 11.

In paragraph [0062] of Japanese Patent Application Laid-Open No. 2006-67197 (see Patent Document 5), a pattern in which the phosphor 43 is printed on the inner surface of the reflection sheet 18 serving as an outer cylinder, or the phosphor 44 is formed on the inner surface of the cover 15. A line light source is disclosed in which a printed pattern is attached or covered so as to be in contact with a light guide.

JP 2002-190919 A (paragraph [0020]) JP 2000-127505 A (paragraph [0023]) Japanese Patent Laying-Open No. 2004-85824 (paragraph [0014], FIG. 2) Japanese Patent Laid-Open No. 10-79835 (paragraph [0015], FIG. 1) JP 2006-67197 A (paragraph [0062])

However, in the device described in Patent Document 1, a high voltage of several kV is applied to the Xe lamp in order to excite and fluoresce the phosphor layer formed on the inner wall surface of the glass tube with ultraviolet light generated by the discharge of Xe gas. There is a problem that a power supply circuit for generating a high voltage is necessary. In addition, since the discharge phenomenon is used, there is a problem that heat generation is large, and the luminous efficiency and luminance of the phosphor are lowered as the lamp temperature rises, and the luminance is greatly changed with time.

Although the thing of patent document 2 can operate | move by a low voltage since it uses blue LED, it is fluorescence of the rod-shaped light source assembly 18 which comprises a part of carriage unit 16 contained in the housing 14 inside. The strips 30 and 32 are mentioned, but the assembly with the peripheral members such as the housing 14 and the carriage unit 16 is not mentioned.

Since the transparent plate (glass plate etc.) 12 which apply | coated the fluorescent substance 13 is arrange | positioned above the LED 11 of ultraviolet light emission, the thing of patent document 3 arrange | positions visible light (VR) and ultraviolet-ray (UV) in the irradiation direction of light. ) And the intensity of the ultraviolet rays is high, the spectrum ratio of the ultraviolet rays to the object to be read is high, and when the intensity of the ultraviolet rays is low, the fluorescence conversion efficiency is deteriorated. In addition, since a large number of LEDs 11 are arranged in an array according to the length in the longitudinal direction (reading width direction), there is a problem that uniform illumination is difficult due to a difference in the light conversion efficiency of each LED 11 due to changes over time. It was.

Since the phosphor 5 is coated on the inner surface of the tube of the light source 1 in the one described in Patent Document 4, there is a variation in the coating thickness of the phosphor 5 coated in a region orthogonal to the sub-scanning direction, ensuring uniformity. There is a problem that it is difficult to do. Further, details regarding the long cylindrical light source 1 being held by the housing frame are not mentioned.

In the device described in Patent Document 5, a pattern in which the phosphor 43 is printed on the inner surface of the reflection sheet 18 as an outer cylinder or a pattern in which the phosphor 44 is printed on the inner surface of the cover 15 is in contact with the light guide. Since it is stuck or covered, there is a problem that the luminous efficiency of the phosphors 43 and 44 is lowered because the thickness of the phosphor layer cannot be sufficiently secured.

The present invention has been made to solve the above-described problems. Even when a long light source is formed, it is possible to obtain illumination uniformity in the longitudinal direction and to improve the conversion efficiency of fluorescent light. An object of the present invention is to obtain an image reading line light source and a light guide unit with high emission intensity.

An image reading line light source according to a first aspect of the present invention includes a light emitting element and the light emitting element disposed at an end, and propagates the light from the light emitting element incident on the inside while reflecting the light along the long axis direction. A rod-shaped light guide, a reflector provided around the light guide with a predetermined gap from the light guide, and provided along the long axis direction; the light guide provided on the light guide side of the reflector; A phosphor layer that absorbs light from the element and emits excited fluorescence.

The line light source for image reading according to a second aspect of the invention is characterized in that the reflection plate has a predetermined gap between the light guide body and surrounds the light guide body, and an opening formed by a long groove along the long axis direction. A narrow light reflection pattern provided in a line along the major axis direction on the outer peripheral surface of the light guide opposite to each end of the opening formed by the long groove with a gap. The apparatus according to claim 1, comprising:

According to a third aspect of the present invention, in the process of light from the light emitting element propagating through the light guide, the phosphor layer is formed from the light emitting element emitted from the surface of the light guide. 2 or more types of composite light that is reflected by the light from the light emitting element and converted into light having an optical wavelength different from that of the light from the light emitting element is generated in the phosphor layer. 2. The device according to claim 1, wherein the irradiated light is transmitted through the inside of the light guide and the irradiated light is irradiated with the composite light including the light from the light emitting element.

According to a fourth aspect of the present invention, there is provided the image reading line light source, wherein the phosphor layer is scattered or specularly reflected by the light reflection pattern in the process in which the light from the light emitting element propagates through the light guide. Two or more types of composite light that captures light from the light emitting element emitted from the surface of the light body, reflects the light from the light emitting element, and is converted into light having an optical wavelength different from that of the light from the light emitting element The light generated by the phosphor layer is transmitted through the inside of the light guide, and the object to be irradiated is irradiated with the composite light including the light from the light emitting element through the opening. As described.

The light guide unit of the invention according to claim 5 is provided with a rod-shaped light guide for propagating incident light incident on the inside from the end while reflecting along the major axis direction, and a predetermined gap is provided between the light guide and the light guide. A reflector that surrounds the light guide and is provided along the long axis direction, and a phosphor layer that is provided on the light guide side of the reflector and that absorbs the incident light and emits excited fluorescence. It is provided.

In the light guide unit of the invention according to claim 6, the reflector has a predetermined gap between the light guide and surrounds the light guide, and has an opening formed by a long groove along the long axis direction. A narrow light reflection pattern provided in a line along the major axis direction on the outer peripheral surface of the light guide opposite to each end of the opening formed by the long groove with a gap. It is a thing of Claim 5 provided.

According to the present invention, even when a long light source is formed, it is possible to obtain illumination uniformity in the longitudinal direction and increase the conversion efficiency of the fluorescent light, thereby increasing the light emission intensity of the image reading line light source and A light guide unit can be obtained.

It is side surface sectional drawing of the line light source for image reading by Embodiment 1 of this invention. It is a perspective view of the line light source for image reading by Embodiment 1 of this invention. It is an expansion | deployment perspective view explaining the structure of the line light source for image reading by Embodiment 1 of this invention. It is sectional drawing of the line light source for image reading by Embodiment 1 of this invention. It is a side view explaining the optical path of the line light source for image reading by Embodiment 1 of this invention. It is sectional drawing explaining the optical path of the line light source for image reading by Embodiment 1 of this invention. It is the expansion | deployment perspective view which changed the light guide body case of the line light source for image reading by Embodiment 1 of this invention. It is sectional drawing which changed the light guide case of the line light source for image reading by Embodiment 1 of this invention. It is a figure explaining the relationship between the thickness of fluorescent substance, and light emission luminance. It is a figure explaining the illumination light emission characteristic of the line light source for image reading by Embodiment 1 of this invention. It is side surface sectional drawing of the line light source for image reading by Embodiment 2 of this invention. It is a perspective view of the line light source for image reading by Embodiment 2 of this invention. It is a figure explaining the characteristic of the ultraviolet cut filter mounted in the line light source for image reading by Embodiment 2 of this invention. It is sectional drawing explaining the size of the reflective pattern of the line light source for image reading by Embodiment 1 or 2 of this invention, Fig.14 (a) shows narrow width size, FIG.14 (b) shows wide width size. It is sectional drawing explaining the position of the reflection pattern of the line light source for image reading by Embodiment 1 or 2 of this invention, Fig.15 (a) shows edge part vicinity, FIG.15 (b) shows center part vicinity. FIGS. 16A and 16B are cross-sectional views illustrating the position of a phosphor layer of an image reading line light source according to Embodiment 3 of the present invention, in which FIG. 16A shows the vicinity of the end and FIG. 16B shows the vicinity of the center. It is sectional drawing explaining the area | region of the fluorescent substance layer of the line light source for image reading by Embodiment 3 of this invention, Fig.17 (a) shows edge part vicinity, FIG.17 (b) shows center part vicinity. It is sectional drawing of the line light source for image reading by Embodiment 4 of this invention, Fig.18 (a) shows edge part vicinity, FIG.18 (b) shows center part vicinity. It is sectional drawing of the line light source for image reading by Embodiment 5 of this invention, Fig.19 (a) shows edge part vicinity, FIG.19 (b) shows center part vicinity. FIG. 20A is a cross-sectional view to which a reflection pattern of an image reading line light source according to Embodiment 5 of the present invention is added, FIG. 20A shows the vicinity of the end portion, and FIG. 20B shows the vicinity of the central portion. It is sectional drawing of the line light source for image reading by Embodiment 6 of this invention, Fig.21 (a) shows edge part vicinity, FIG.21 (b) shows center part vicinity. It is sectional drawing which added the reflection pattern of the line light source for image reading by Embodiment 6 of this invention, Fig.22 (a) shows edge part vicinity, FIG.22 (b) shows center part vicinity. It is sectional drawing of the line light source for image reading by Embodiment 7 of this invention, Fig.23 (a) shows edge part vicinity, FIG.23 (b) shows center part vicinity. FIG. 24A is a cross-sectional view to which a reflection pattern of an image reading line light source according to Embodiment 7 of the present invention is added. FIG. 24A shows the vicinity of the end portion, and FIG. It is sectional drawing of the center part vicinity of the line light source for image reading by Embodiment 8 of this invention. It is side surface sectional drawing of the line light source for image reading by Embodiment 8 of this invention.

Embodiment 1 FIG.
An image reading line light source according to Embodiment 1 of the present invention will be described with reference to FIGS. FIG. 1 is a side sectional view of an image reading line light source according to Embodiment 1 of the present invention. FIG. 2 is a perspective view of the line light source for image reading according to Embodiment 1 of the present invention. FIG. 3 is an exploded perspective view illustrating the configuration of the image reading line light source according to the first embodiment of the present invention. 4 is a cross-sectional view of the image reading line light source according to Embodiment 1 of the present invention as viewed from the end of FIG.

The LED light source 1 is a light source having a wavelength of about 430 nm to 470 nm using an LED light emitting element that emits blue light. The LED circuit 2 includes a connector 2b for mounting the LED light source 1 on a substrate 2a such as an epoxy material and supplying power from the outside to the LED light source 1. The light guide 3 is formed by molding a member having a refractive index (n) of 1.5 or more, such as transparent soda glass, transparent resin, or transparent sapphire having a transmittance of about 80%, into an end portion. The light from the LED light source 1 is incident from this end, and the blue light incident on the inside is guided along the longitudinal direction (long axis direction). A path of light passing through the inside of the light guide 3 in the long axis direction is called a light guide path, and a path of light passing through the direction orthogonal to the long axis direction of the light guide 3 is called a transverse path (transmission path). .

In the example shown in FIG. 4, white in which a phosphor layer (phosphor) 5 is applied to the inner circumferential surface with a predetermined gap (d) of about 0.1 mm from the outer circumferential surface of the cylindrical light guide 3. The reflector (light guide body) 6 is installed so as to surround the light guide 3. That is, the outer peripheral surface of the light guide 3 and the inner peripheral surface of the reflection plate 6 are configured in a concentric shape with the same central axis with respect to the reading region (effective reading width) in the long axis direction.

The reflector 6 is provided with an opening 6a serving as a take-out port for emitting light to the irradiated body by forming a long groove having a constant width in a direction perpendicular to the long axis direction along the long axis direction. The end of the opening 6a is called a long groove end. On the outer peripheral surface of the light guide 3 facing each end of each long groove with a predetermined gap, a white light reflecting member for silk printing or a direct groove is formed in the light guide 3 along the long axis direction. The light reflection patterns 4 are formed in parallel with each other using the lenticular lens or the prism pattern. Therefore, part of the blue light passing through the light guide path of the light guide 3 is scattered or specularly reflected by the light reflection pattern 4, passes through the transverse path inside the light guide 3, and exits from the surface of the light guide 3. And captured by the phosphor layer 5 of the reflector 6.

A phosphor layer 5 having a thickness (t) of about 50 μm is applied to the inner surface of the reflecting plate 6. The phosphor layer 5 is coated with a mixture of a phosphor emitting red light having a wavelength of about 600 nm and a phosphor emitting green light having a wavelength of about 525 nm. The phosphor layer 5 captures blue light, A part of the blue light is reflected and crosses the inside of the light guide 3 and is irradiated to the irradiated body from the opening 6a. The other blue light is absorbed by the phosphor layer 5 and emits excited fluorescence. That is, the phosphor layer 5 generates two types of composite light converted into light having a wavelength different from that of blue light.

The generated fluorescence traverses the inside of the light guide 3 and is irradiated to the irradiated body as composite light from the opening 6a. Accordingly, pseudo white light in which blue light, red light, and green light are mixed is illuminated on the irradiated object. As shown in FIG. 3, the light guide 3 is fixed by projections 6b provided at both ends and the center of the reflection plate 6.

The line light source (line light source for image reading) stores the LED light source 1 placed on the substrate 2a of the LED circuit 2 on one end side of the hollow portion of the holder 7 having a hollow portion, and the light guide 3 on the other end side. It is configured by inserting the end of the incorporated reflector 6. In FIG. 1, the holders 7 are provided at both ends of the reflector 6, and blue light emitted from the LED light source 1 enters from both sides of the light guide 3.

Next, the relationship between the LED light source 1 and the holder 7 will be described. The LED circuit 2 mounted with the blue light emitting LED light source 1 provided at the end of the light guide 3 is fixed by a holder 7 which is a holding mechanism thereof, and the LED circuit 2 is attached to the light guide 3 and the reflection plate 6. At the end of the light guide 3, the light guide 3 is attached so that the optical positions centering on the irradiation axis through which light passes are aligned, and the LED circuit 2 is provided with one or more blue LEDs. Further, the structure of the holder 7 allows the LED light source 1 to maintain a predetermined distance from the end of the light guide 3 so that the blue light emitted from the LED light source 1 can be stably taken into the light guide 3. Composed.

Further, the holder 7 has a two-stage fitting insertion structure shown in FIG. 1 to prevent the light guide 3 and the reflector 6 from being displaced, and the holder 7 is positioned at both ends of the light guide 3. Yes. Further, the fitting of the holder 7 to the light guide 3 is, for example, a depth of 2 mm or more when the diameter of the light guide 3 is 4 mm, and the blue light incident from the LED light source 1 is entirely against the surface of the light guide 3. Only light incident at an angle smaller than the reflection angle is incident on the inside of the light guide 3, and the direct light of the LED light source 1 is not directly involved as illumination light outside the holder 7.

Next, the operation of the line light source will be described with reference to FIGS. FIG. 5 is a side view for explaining the optical path of the image reading line light source according to the first embodiment of the present invention. FIG. 6 is a sectional view for explaining the optical path of the line light source for image reading according to Embodiment 1 of the present invention.

In the process in which light emitted from the LED light source 1 is guided toward the other end side of the cylindrical light guide 3 formed of a transparent material, a light reflection pattern 4 provided on the light guide 3. Then, the light is scattered or specularly reflected and irradiated onto the phosphor layer 5. The fluorescence emitted from the phosphor layer 5 and the blue light reflected by the phosphor layer 5 are mixed, and the fluorescence is emitted from the opening 6a of the reflector 6 to the irradiated object such as a document via the light guide 3. Irradiate with blue light.

Since the light guide 3 has a higher refractive index than the external space, the light incident from the end of the light guide 3 is larger than the total reflection angle when reaching the surface of the mirror-shaped light guide 3. It is incident at an angle and propagates through the light guide in the light guide 3 by being totally reflected by the surface.

Part of the light is reflected by the light reflection pattern 4, the reflection angle is changed, and the light is emitted from the surface of the light guide 3 to the outside at an angle smaller than the total reflection angle. This light is applied to the phosphor layer 5 applied to the inner surface of the reflector 6. The reflector 6 serves as a support substrate for the phosphor layer 5 formed on the inner surface of the reflector 6 on the light guide 3 side of the reflector 6.

The outer peripheral surface of the light guide 3 and the inner peripheral surface of the reflector 6 have a predetermined gap (gap), and the stability of the position with respect to the light guide 3 is ensured by making this gap constant. Further, as shown in FIGS. 3 and 4, the reflector 6 has protrusions 6b having a small contact area with the light guide 3 having a height of about 0.1 mm on the inner surfaces of the three portions at both ends and the center. When the protrusion 6b and the light guide 3 are in close contact with each other, a predetermined gap (d> t) is provided between the phosphor layer 5 formed on the inner surface of the reflector 6 and the light guide 3. To maintain.

The phosphor layer 5 is formed of a dye or pigment having a fluorescence wavelength such as red or green (yellowish green), and is mainly formed on the inner surface of the reflection plate 6 facing the light reflection pattern 4 of the light guide 3. . The blue light emitted from the light guide 3 to the phosphor layer 5 is a crossing path of the light guide 3 by combining the fluorescence from the phosphor layer 5 and the diffuse reflection of the blue light reflected from the surface of the phosphor layer 5. And is emitted from the opening 6a of the reflecting plate 6 to illuminate the irradiated object with white light.

In the first embodiment, the protrusions 6b of the reflecting plate 6 are provided at both ends and the center of the reflecting plate 6. However, as shown in FIGS. 7 and 8, they are provided uniformly and continuously in the major axis direction. Also good. That is, as a mechanism for maintaining a gap between the light guide 3 and the reflecting plate 6 coated with the phosphor layer 5, in the first embodiment, protrusions 6b having a predetermined interval in the major axis direction are formed on the inner surface of the reflecting plate 6. However, a triangular prism or semi-cylindrical projection 6c is continuously formed in a line shape in the major axis direction of the reflecting plate 6 to form a protruding portion 6b of the reflecting plate 6, and the position of the light guide 3 and the phosphor layer 5 A mechanism for maintaining the relationship may be used. In this case, since the short-axis cross-sectional shape of the reflecting plate 6 is the same in the long-axis direction, the reflecting plate 6 can be easily molded.

FIG. 9 is a diagram for explaining the relationship between the thickness of the phosphor and the light emission luminance. Although the phosphor layer 5 has a thickness of about 50 μm, as shown in FIG. 9, the conversion efficiency for generating fluorescence by forming the phosphor layer 5 with such a thickness that the emission intensity is saturated when irradiated with blue light. As a result, it is possible to save energy and to prevent the emission intensity from becoming uneven due to the variation in the film thickness of the phosphor layer 5.

FIG. 10 is a diagram for explaining the illumination emission characteristics of the image reading line light source according to the first embodiment of the present invention. In FIG. 10, the peak wavelength of about 450 nm and the composite light emitted by the phosphor over about 500 to 630 nm are combined to give white light.

In the image reading line light source having the above structure, the blue light reflected by the phosphor layer 5 and the composite light generated by the phosphor layer 5 are mixed and transmitted through the inside of the light guide 3. White illumination light is given to the irradiated object from the opening 6a. Further, since the light guide 3 has a cylindrical shape, the reflected light reflected from the surface of the phosphor layer 5 and the generated fluorescence are collected by the light guide 3 and the irradiated object is subjected to the lens effect. There is an effect that the illumination illuminance is improved.

Embodiment 2. FIG.
In the first embodiment, the configuration of the line light source using the blue LED has been described. In the second embodiment, the configuration of the line light source using the ultraviolet LED will be described with reference to FIGS. 11 and 12. FIG. 11 is a side sectional view of an image reading line light source according to Embodiment 2 of the present invention. FIG. 12 is a perspective view of an image reading line light source according to Embodiment 2 of the present invention.

The LED light source 11 is a light source having a wavelength of about 350 nm to 380 nm using an LED light emitting element that emits ultraviolet rays. The LED circuit 2 includes a connector 2b for mounting the LED light source 11 on a substrate 2a such as an epoxy material and supplying power from the outside to the LED light source 11. The light guide 3 is formed by molding a member having a refractive index (n) of 1.5 or more, such as transparent soda glass, transparent resin, or transparent sapphire having a transmittance of about 80%, into an end portion. , And the light from the LED light source 11 is incident from this end, and the ultraviolet light (ultraviolet light) incident on the inside is guided along the longitudinal direction (long axis direction). A path of light passing through the inside of the light guide 3 in the long axis direction is called a light guide path, and a path of light passing through the direction orthogonal to the long axis direction of the light guide 3 is called a transverse path (transmission path). .

A white reflector (light guide body case) 6 in which a fluorescent material is applied to the inner peripheral surface with a predetermined gap of about 0.1 mm with respect to the outer peripheral surface of the cylindrical light guide 3 is used as the light guide 3. Since the configuration installed so as to surround is the same as that described in the first embodiment, detailed description thereof is omitted.

The reflector 6 is provided with an opening 6a serving as a take-out port for emitting light to the irradiated body by forming a long groove having a constant width in a direction perpendicular to the long axis direction along the long axis direction. The end of the opening 6a is called a long groove end. On the outer peripheral surface of the light guide 3 facing each end of each long groove with a predetermined gap, a white light reflecting member for silk printing or a direct groove is formed in the light guide 3 along the long axis direction. The light reflection patterns 4 are formed in parallel with each other using the lenticular lens or the prism pattern. Accordingly, a part of the ultraviolet light passing through the light guide path of the light guide 3 is scattered or specularly reflected by the light reflection pattern 4 and transmitted through the transverse path inside the light guide 3 and emitted from the surface of the light guide 3. And captured by the phosphor layer 51 of the reflector 6.

A phosphor layer 51 having a thickness (t) of about 50 μm is applied to the inner surface of the reflector 6. The phosphor layer 51 is coated with a mixture of a phosphor emitting red light having a wavelength of about 600 nm, a phosphor emitting green light having a wavelength of about 525 nm, and a phosphor emitting blue light having a wavelength of about 450 nm. Ultraviolet light is captured by the phosphor layer 51, a part of the ultraviolet light is reflected, crosses the inside of the light guide 3, and is irradiated to the irradiated object from the opening 6 a. Other ultraviolet light is absorbed by the phosphor layer 51 and emits excited fluorescence. That is, the phosphor layer 51 generates three types of composite light converted into light having a wavelength different from that of ultraviolet light.

The generated fluorescence traverses the inside of the light guide 3 and is irradiated to the irradiated body as composite light from the opening 6a. Accordingly, pseudo white light in which blue light, red light, and green light are mixed is illuminated on the irradiated object.

The line light source (line light source for image reading) accommodates the LED light source 11 placed on the substrate 2a of the LED circuit 2 on one end side of the hollow portion of the holder 7 having a hollow portion, and the light guide 3 on the other end side. It is configured by inserting the end of the incorporated reflector 6. In FIG. 11, the holder 7 is provided on both ends of the reflector 6, and the ultraviolet light emitted from the LED light source 11 enters from both sides of the light guide 3. Note that the relationship between the LED light source 11 and the holder 7 and the operation of the line light source are the same as those described in the first embodiment, and a description thereof will be omitted. 11 and 12, the same reference numerals as those in FIGS. 1 and 2 denote the same or corresponding parts.

In the second embodiment, a line is formed from the opening 6a of the reflector 6 along the long axis direction on the outer peripheral surface of the light guide 3 sandwiched between the light reflection patterns 4 so that ultraviolet light does not enter the irradiated body. An ultraviolet light shielding pattern (ultraviolet cut filter) 8 for shielding the emitted ultraviolet light is provided. In other words, the ultraviolet light shielding pattern 8 is provided on the outer peripheral surface of the light guide 3 sandwiched between the light reflecting patterns 4 to shield the ultraviolet light emitted in a line shape from the opening 6a of the reflecting plate 6 along the long axis direction. . As shown in FIG. 13, the ultraviolet cut filter 8 has a cut-off wavelength in the vicinity of about 430 nm, cuts a wavelength on the short wavelength side of 430 nm or less, and guides a filter material that transmits light on the long wavelength side including blue light. Used by applying or vapor-depositing on the body 3.

Since the ultraviolet light reflected by the phosphor layer 51 and the like is not necessary as illumination light, only the fluorescent visible light that has passed through the ultraviolet cut filter 8 is irradiated to the irradiated object. In the second embodiment, it is possible to obtain a light emission spectrum having no strong light emission peak in the blue light-emitting component with respect to the light emission spectrum shown in FIG. 10 using the blue LED described in the first embodiment. That is, the illumination has a flat emission spectrum in the visible light region.

As described above, in the line light source for image reading according to the second embodiment, the ultraviolet light reaching the opening 6 a is shielded by the ultraviolet cut filter 8, and the composite light generated by the phosphor layer 51 passes through the light guide 3. The white illumination light is transmitted through the opening 6a of the reflecting plate 6 to the irradiated object. Further, since the light guide 3 has a cylindrical shape, the fluorescence generated by the phosphor layer 5 is condensed by the light guide 3 and the illumination effect on the irradiated body is improved by the lens effect. There is also.

In Embodiments 1 and 2, the width of the light reflection pattern 4 is not mentioned, but the width of the light reflection pattern 4 is as small as W1 = 0.2 mm as shown in FIG. As shown in (b), a relatively wide narrow pattern of W2 = 0.3 mm is appropriate.

In the first and second embodiments, the position of the light reflection pattern 4 is provided on the outer peripheral surface of the light guide 3 facing the respective end portions of the opening 6a formed by the long groove with a gap therebetween. As shown in FIGS. 15A and 15B, the pattern 4 has the same effect as that described in the first and second embodiments even when a part of the pattern 4 enters the opening 6a side.

Embodiment 3 FIG.
FIG. 16 is a cross-sectional view for explaining the position of the phosphor layer of the line light source for image reading according to Embodiment 3 of the present invention. FIG. 16 (a) is near the end, and FIG. 16 (b) is near the center. Indicates. FIGS. 17A and 17B are sectional views for explaining the region of the phosphor layer of the line light source for image reading according to the third embodiment of the present invention. FIG. 17A shows the vicinity of the end portion, and FIG. Indicates.

In the first embodiment, the phosphor layer 5 is applied to the entire inner surface of the reflector 6. However, in the third embodiment, a plurality of phosphor layers 5 having a constant width are formed in the direction perpendicular to the major axis direction along the major axis direction. It is provided in the form of individual lines, and a slit portion is provided between the adjacent phosphor layers 5. Further, at least the inner surface area of the reflector 6 on which the phosphor layer 5 is not coated is shielded with a light absorbing material such as black, thereby absorbing blue light and reducing the light emission luminance of the blue LED light emitting component shown in FIG. Thus, the luminance of the phosphor layer light emitting component can be brought close to. That is, the luminance of the white light emission spectrum can be adjusted by applying a black plastic resin to the light guide case (reflecting plate) 6.

In the first embodiment, the phosphor layer is applied to the entire inner surface of the reflector 6. However, as shown in FIG. 17, the application region of the phosphor layer 5 is not limited to the entire inner surface of the reflector 6 and faces the opening 6 a. By using the black light guide case 6 by providing the phosphor layer 5 having a width of 2 mm and about 3 lines mainly in the region of the reflecting plate 6 to be emitted, the light emission luminance of the blue LED light emitting component can be further reduced.

Embodiment 4 FIG.
In the first embodiment, the configuration of the line light source using the cylindrical light guide has been described. In the fourth embodiment, the configuration of the line light source using the light guide having an elliptical short-side cross section is illustrated. 18 will be described. 18A and 18B are cross-sectional views of an image reading line light source according to Embodiment 4 of the present invention. FIG. 18A shows the vicinity of the end, and FIG. 18B shows the vicinity of the center.

A white reflector (light guide case) 61 in which a phosphor is applied to the inner peripheral surface with a predetermined gap of about 0.1 mm from the outer peripheral surface of the rod-shaped light guide 31 having an elliptical short-side cross section. Is the same as that described in the first embodiment except for the configuration that is installed so as to surround the light guide 31.

The reflecting plate 61 is provided with an opening 61a serving as a take-out port for emitting light to the irradiated body by forming a long groove having a constant width in a direction orthogonal to the long axis direction along the long axis direction. The end of the opening 61a is referred to as a long groove end. On the outer peripheral surface of the light guide 31 facing each long groove end portion with a predetermined gap, a white light reflecting member for silk printing or a light guide 3 is directly cut along the long axis direction. The light reflection patterns 4 are formed in parallel with each other using the lenticular lens or the prism pattern. Accordingly, part of the blue light passing through the light guide path of the light guide 31 is scattered or specularly reflected by the light reflection pattern 4, passes through the transverse path inside the light guide 31, and is emitted from the surface of the light guide 31. And captured by the phosphor layer 5 of the reflector 61.

A phosphor layer 5 having a thickness (t) of about 50 μm is applied to the inner surface of the reflecting plate 61. The phosphor layer 5 is coated with a mixture of a phosphor emitting red light having a wavelength of about 600 nm and a phosphor emitting green light having a wavelength of about 525 nm. The phosphor layer 5 captures blue light, A part of the blue light is reflected and crosses the inside of the light guide 31 and is irradiated to the irradiated body from the opening 61a. The other blue light is absorbed by the phosphor layer 5 and emits excited fluorescence. That is, the phosphor layer 5 generates two types of composite light converted into light having a wavelength different from that of blue light.

The generated fluorescence traverses the inside of the light guide 31 and is irradiated to the irradiated body as composite light from the opening 61a. Accordingly, pseudo white light in which blue light, red light, and green light are mixed is illuminated on the irradiated object. Since the relationship between the LED light source and the holder and the operation of the line light source are the same as those described in the first embodiment, the description thereof is omitted. 18, the same reference numerals as those in FIG. 4 denote the same or corresponding parts.

In the image reading line light source having the above structure, the blue light reflected by the phosphor layer 5 and the composite light generated by the phosphor layer 5 are mixed and transmitted through the light guide 31, White illumination light is given to the irradiated object from the opening 61a. Further, since the cross section of the light guide 31 has an elliptical shape, the reflected light reflected on the surface of the phosphor layer 5 and the generated fluorescence are collected by the light guide 31 and are subject to the lens effect. This has the effect of improving the illumination illuminance on the irradiating body, and has an advantage that a large number of LED light sources can be mounted in the major axis direction of the ellipse because the section is elliptical.

Embodiment 5 FIG.
In the first embodiment, the configuration of a line light source using a cylindrical light guide has been described. In the fifth embodiment, a line light source in which a short-axis-side cross section is provided with a notch in a light guide having an elliptical cross section. The configuration will be described with reference to FIGS. 19 and 20. 19 is a cross-sectional view of an image reading line light source according to Embodiment 5 of the present invention. FIG. 19A shows the vicinity of the end portion, and FIG. 19B shows the vicinity of the center portion. 20 is a cross-sectional view to which a reflection pattern of an image reading line light source according to Embodiment 5 of the present invention is added. FIG. 20 (a) shows the vicinity of the end portion, and FIG. 20 (b) shows the vicinity of the central portion.

In FIG. 19, a notch 62c is provided in a part of the rod-shaped light guide 32 whose minor axis side section is elliptical, and the light reflection pattern 4 is provided along the major axis on both sides of the notch 62c. A white reflecting plate (light guide body case) 62 in which the phosphor layer 5 is applied to the inner peripheral surface with a predetermined gap of about 0.1 mm from the outer peripheral surface of the light guide 32 excluding the notch portion 62c is guided. Since the configuration other than that installed so as to surround the light body 32 is the same as that described in the first embodiment, the description thereof is omitted.

The reflector 62 is provided with an opening 62a serving as a take-out port for emitting light to the irradiated body by forming a long groove having a constant width in a direction perpendicular to the long axis direction along the long axis direction. The end of the opening 62a is called a long groove end. A cutout portion 62c on the outer peripheral surface of the light guide 32 that is spaced apart and opposed to each long groove end portion is directly cut into the white light reflecting member for silk printing or the light guide 32 along the long axis direction. The light reflection patterns 4 are formed in parallel with each other using the lenticular lens or prism pattern formed in (1). Accordingly, part of the blue light passing through the light guide path of the light guide 32 is scattered or specularly reflected by the light reflection pattern 4, passes through the transverse path inside the light guide 32, and is emitted from the surface of the light guide 32. And captured by the phosphor layer 5 of the reflector 62.

A phosphor layer 5 having a thickness (t) of about 50 μm is applied to the inner surface of the reflector 62. The phosphor layer 5 is coated with a mixture of a phosphor emitting red light having a wavelength of about 600 nm and a phosphor emitting green light having a wavelength of about 525 nm. The phosphor layer 5 captures blue light, A part of the blue light is reflected, crosses the inside of the light guide 32, and is irradiated to the irradiated body from the opening 62a. The other blue light is absorbed by the phosphor layer 5 and emits excited fluorescence. That is, the phosphor layer 5 generates two types of composite light converted into light having a wavelength different from that of blue light.

The generated fluorescence crosses the inside of the light guide 32 and is irradiated to the irradiated body as composite light from the opening 62a. Accordingly, pseudo white light in which blue light, red light, and green light are mixed is illuminated on the irradiated object. Since the relationship between the LED light source and the holder and the operation of the line light source are the same as those described in the first embodiment, the description thereof is omitted. 19, the same reference numerals as those in FIG. 4 denote the same or corresponding parts.

In the image reading line light source having the above structure, the blue light reflected by the phosphor layer 5 and the composite light generated by the phosphor layer 5 are mixed and transmitted through the light guide 32, White illumination light is given to the irradiated object from the opening 62a. Furthermore, since the cross section of the light guide 32 has an elliptical shape, the reflected light reflected by the surface of the phosphor layer 5 and the generated fluorescence are collected by the light guide 32 and are subject to the lens effect. This has the effect of improving the illumination illuminance to the irradiating body and has an advantage that a large number of LED light sources can be mounted in the major axis direction of the ellipse since the short-axis side section of the light guide 32 is elliptical. Further, as shown in FIG. 20, the light reflection pattern 41 is added to the outer peripheral surface of the light guide 32 facing the light reflection pattern 4 installed on the opening 62a side of the light guide 32, and the light is emitted from the opening 62a. The amount of blue light irradiation can be increased. Also, the amount of blue light emitted can be adjusted by changing the installation position of the light reflection pattern 41 installed on the outer peripheral surface of the light guide 32.

Embodiment 6 FIG.
In the first embodiment, the configuration of the line light source using the cylindrical light guide has been described, but in the sixth embodiment, the line light source in which the short-axis side cross section has a pentagonal light guide and a notch is provided. The configuration will be described with reference to FIGS. 21 and 22. 21 is a cross-sectional view of an image reading line light source according to Embodiment 6 of the present invention. FIG. 21 (a) shows the vicinity of the end portion, and FIG. 21 (b) shows the vicinity of the central portion. FIGS. 22A and 22B are sectional views to which a reflection pattern of the line light source for image reading according to the sixth embodiment of the present invention is added. FIG. 22A shows the vicinity of the end portion, and FIG. 22B shows the vicinity of the central portion.

In FIG. 21, a notch 63c is provided in a part of a rod-shaped light guide 33 having a pentagonal cross section on the short axis side, and the light reflection pattern 4 is provided along the major axis on both sides of the notch 63c. A white reflector (light guide case) 63 in which the phosphor layer 5 is applied to the inner peripheral surface with a predetermined gap of about 0.1 mm from the outer peripheral surface of the light guide 33 excluding the notch 63c is guided. Since the configuration other than that installed so as to surround the light body 33 is the same as that described in the first embodiment, the description thereof is omitted.

The reflector 63 is provided with an opening 63a serving as a take-out port for emitting light to the irradiated body by forming a long groove having a constant width in a direction perpendicular to the long axis direction along the long axis direction. The end of the opening 63a is called a long groove end. A notch 63c on the outer peripheral surface of the light guide 33 that is spaced apart from and opposed to each long groove end is directly cut into the white light reflecting member for silk printing or the light guide 33 along the long axis direction. The light reflection patterns 4 are formed in parallel with each other using the lenticular lens or prism pattern formed in (1). Therefore, part of the blue light passing through the light guide path of the light guide 33 is scattered or specularly reflected by the light reflection pattern 4, passes through the transverse path inside the light guide 33, and exits from the surface of the light guide 33. And captured by the phosphor layer 5 of the reflector 63.

The phosphor layer 5 having a thickness (t) of about 50 μm is applied to the inner surface of the reflector 63. The phosphor layer 5 is coated with a mixture of a phosphor emitting red light having a wavelength of about 600 nm and a phosphor emitting green light having a wavelength of about 525 nm. The phosphor layer 5 captures blue light, A part of the blue light is reflected, crosses the inside of the light guide 33 and is irradiated to the irradiated body from the opening 63a. The other blue light is absorbed by the phosphor layer 5 and emits excited fluorescence. That is, the phosphor layer 5 generates two types of composite light converted into light having a wavelength different from that of blue light.

The generated fluorescence traverses the inside of the light guide 33 and is irradiated to the irradiated body as composite light from the opening 63a. Accordingly, pseudo white light in which blue light, red light, and green light are mixed is illuminated on the irradiated object. Since the relationship between the LED light source and the holder and the operation of the line light source are the same as those described in the first embodiment, the description thereof is omitted. In FIG. 21, the same reference numerals as those in FIG. 4 denote the same or corresponding parts.

In the image reading line light source having the above structure, the blue light reflected by the phosphor layer 5 and the composite light generated by the phosphor layer 5 are mixed and transmitted through the light guide 33, White illumination light is given to the irradiated body from the opening 63a. In the sixth embodiment, the notch 63c of the light guide 33 serves as a light exit surface. Further, as shown in FIG. 22, the blue light emitted from the opening 63a by adding the light reflection pattern 41 to the outer peripheral surface of the light guide 33 facing the reflection pattern 4 installed on the opening 63a side of the light guide 33. The amount of light irradiation can be increased. Moreover, the emission amount of blue light can be adjusted by changing the installation position of the reflection pattern 41 installed on the outer peripheral surface of the light guide 33.

Embodiment 7 FIG.
In the sixth embodiment, the light reflection pattern is provided in the notch portion of the light guide having a pentagonal cross section on the short axis side. However, in the seventh embodiment, the light reflection pattern is provided on the surface of the light guide other than the notch portion. The configuration of the provided line light source will be described with reference to FIGS. FIG. 23 is a cross-sectional view of an image reading line light source according to Embodiment 7 of the present invention. FIG. 23 (a) shows the vicinity of the end, and FIG. 23 (b) shows the vicinity of the center. 24 is a cross-sectional view to which a reflection pattern of an image reading line light source according to Embodiment 7 of the present invention is added. FIG. 24 (a) shows the vicinity of the end portion, and FIG. 24 (b) shows the vicinity of the central portion.

In FIG. 23, a notch 63c is provided in a part of a rod-shaped light guide 33 having a pentagonal cross section on the short axis side, and is guided along the major axis direction of the light guide 33 located outside the notch 63c. A white reflection in which a light reflecting pattern 4 is provided on the light body 33 and a fluorescent material is applied to the inner peripheral surface with a predetermined gap of about 0.1 mm from the outer peripheral surface of the light guide 33 excluding the notch 63c. Except for the configuration in which the plate (light guide case) 63 is installed so as to surround the light guide 33, the description is omitted because it is the same as that described in the first embodiment.

The reflector 63 is provided with an opening 63a serving as a take-out port for emitting light to the irradiated body by forming a long groove having a constant width in a direction perpendicular to the long axis direction along the long axis direction. The end of the opening 63a is called a long groove end. The side of the light guide 33 that is adjacent to the notch 63c on the outer peripheral surface of the light guide 33 that is opposed to the end of each long groove is adjacent to the notch 63c and silks along the long axis direction. The light reflecting patterns 4 are formed in parallel to each other using a white light reflecting member for printing or a lenticular lens or a prism pattern formed directly on the light guide 33 by kerfs. Therefore, part of the blue light passing through the light guide path of the light guide 33 is scattered or specularly reflected by the light reflection pattern 4, passes through the transverse path inside the light guide 33, and exits from the surface of the light guide 33. And captured by the phosphor layer 5 of the reflector 63.

The phosphor layer 5 having a thickness (t) of about 50 μm is applied to the inner surface of the reflector 63. The phosphor layer 5 is coated with a mixture of a phosphor emitting red light having a wavelength of about 600 nm and a phosphor emitting green light having a wavelength of about 525 nm. The phosphor layer 5 captures blue light, A part of the blue light is reflected, crosses the inside of the light guide 33 and is irradiated to the irradiated body from the opening 63a. The other blue light is absorbed by the phosphor layer 5 and emits excited fluorescence. That is, the phosphor layer 5 generates two types of composite light converted into light having a wavelength different from that of blue light.

The generated fluorescence traverses the inside of the light guide 33 and is irradiated to the irradiated body as composite light from the opening 63a. Accordingly, pseudo white light in which blue light, red light, and green light are mixed is illuminated on the irradiated object. Since the relationship between the LED light source and the holder and the operation of the line light source are the same as those described in the first embodiment, the description thereof is omitted. 23, the same reference numerals as those in FIG. 21 denote the same or corresponding parts.

In the image reading line light source having the above structure, the blue light reflected by the phosphor layer 5 and the composite light generated by the phosphor layer 5 are mixed and transmitted through the light guide 33, White illumination light is given to the irradiated body from the opening 63a. In the seventh embodiment, the notch 63c of the light guide 33 serves as a light exit surface, but the blue light transmitted through the light reflection pattern 4 and leaking to the opening 63a is reduced, and the notch of the light guide 33 is reduced. The area of the emission region of the light emitted from the portion 63c can be increased. Further, as shown in FIG. 24, the light reflection pattern 41 is added to the outer peripheral surface of the light guide 33 facing the light reflection pattern 4 disposed on the opening 63a side of the light guide 33, and the light is emitted from the opening 63a. The amount of blue light irradiation can be increased. Moreover, the emission amount of blue light can be adjusted by changing the installation position of the reflection pattern 41 installed on the outer peripheral surface of the light guide 33.

Embodiment 8 FIG.
In the seventh embodiment, the light reflection pattern is provided outside the notch portion of the light guide having a pentagonal short-axis cross section. However, in the eighth embodiment, the notch portion of the light guide is chamfered (C chamfering). The configuration of the line light source will be described with reference to FIGS. 25 and 26. FIG. FIG. 25 is a cross-sectional view of the vicinity of the center of an image reading line light source according to the eighth embodiment of the present invention. FIG. 26 is a side sectional view of an image reading line light source according to the eighth embodiment of the present invention.

In FIG. 25, a notch portion 64c is provided in a part of the rod-shaped light guide 34 whose short-axis side section is a quadrangle, and light is guided along the long-axis direction of the light guide 34 located outside the notch 64c. A white reflector in which a light reflecting pattern 4 is provided on the body 34 and a phosphor is applied to the inner peripheral surface with a predetermined gap of about 0.1 mm from the outer peripheral surface of the light guide 34 excluding the notch 64c. (Light guide case) Except for the configuration in which the light guide case 64 is installed so as to surround the light guide 34, the description is omitted because it conforms to that described in the first embodiment.

The reflecting plate 64 is provided with an opening 64a serving as a take-out port for emitting light to the irradiated body by forming a long groove having a constant width in a direction perpendicular to the long axis direction along the long axis direction. The end of the opening 64a is called a long groove end. The side of the light guide 34 adjacent to the notch 64c on the outer peripheral surface of the light guide 34 facing each long groove end with a predetermined gap is adjacent to the notch 64c in the long axis direction. A light reflecting pattern 4 is formed in parallel with each other using a white light reflecting member for silk printing or a lenticular lens or a prism pattern formed in the light guide 34 directly by a kerf. Accordingly, part of the blue light passing through the light guide path of the light guide 34 is scattered or specularly reflected by the light reflection pattern 4, passes through the transverse path inside the light guide 34, and is emitted from the surface of the light guide 34. And captured by the phosphor layer 5 of the reflector 64.

A phosphor layer 5 having a thickness (t) of about 50 μm is applied to the inner surface of the reflector 64. The phosphor layer 5 is coated with a mixture of a phosphor emitting red light having a wavelength of about 600 nm and a phosphor emitting green light having a wavelength of about 525 nm. The phosphor layer 5 captures blue light, A part of the blue light is reflected, crosses the inside of the light guide 34 and is irradiated to the irradiated body from the opening 64a. The other blue light is absorbed by the phosphor layer 5 and emits excited fluorescence. That is, the phosphor layer 5 generates two types of composite light converted into light having a wavelength different from that of blue light.

The generated fluorescence traverses the inside of the light guide 34 and is irradiated to the irradiated body as composite light from the opening 64a. Accordingly, pseudo white light in which blue light, red light, and green light are mixed is illuminated on the irradiated object. Since the relationship between the LED light source and the holder and the operation of the line light source are the same as those described in the first embodiment, the description thereof is omitted. 25, the same reference numerals as those in FIG. 4 denote the same or corresponding parts.

In the image reading line light source having the above structure, the blue light reflected by the phosphor layer 5 and the composite light generated by the phosphor layer 5 are mixed and transmitted through the light guide 34, White illumination light is given to the irradiated object from the opening 64a. In the eighth embodiment, the cutout portion 64 c of the light guide 34 serves as a light emission surface, and the cutout portion 64 c chamfers a part of the light guide 34.

FIG. 26 is a side cross-sectional view of the line light source when the cross-sectional area shown in FIG. 25 is viewed from the long axis direction, and white light is concentrated on the object to be irradiated from the chamfered portion (notch portion) 64c of the light guide 34. By irradiating, there is an advantage that a line light source having a large illumination illuminance can be obtained.

In the third to eighth embodiments, the line light source using mainly blue LEDs has been described. However, even in the case of the line light source using ultraviolet LEDs described in the second embodiment, the relationship between the LED light source and the holder and the operation of the light source. Is the same.

In the first to eighth embodiments, the phosphor layers 5 and 51 are described as a mixture (blend) of fluorescent materials. However, the phosphor layers 5 and 51 are dividedly formed, and the phosphor layers 5 and 51 are formed. Monochromatic light emission may be performed, and the phosphor material has mainly been described for red light emission, green light emission, and blue light emission, but is not limited to these light emission colors, and phosphor materials such as orange and yellow-green light emission colors are used. An image reading line light source may be configured.

1. LED light source (blue LED)
2 .... LED circuit 2a ... PCB 2b ... Connector (external terminal)
3. Light guide (cylindrical light guide)
4. Light reflection pattern (light guide reflection pattern)
5..Phosphor layer 6..Reflector (light guide case) 6a..Opening part 6b..Protrusion part 6c..Protrusion part 7..Holder 8..Ultraviolet light cut filter (ultraviolet cut pattern)
11. LED light source (ultraviolet light source)
31 .. Light guide (elliptical light guide) 32 .. Light guide (elliptical light guide)
33 .. Light guide (pentagonal light guide) 34 .. Light guide (square prism chamfered light guide)
41 .. Light reflection pattern 51 .. Phosphor layer 61 .. Reflector (light guide case)
61a ··· Opening portion 61b ·· Protruding portion 62 ·· Reflector (light guide case)
62a ·· Opening portion 62b ·· Protruding portion 62c ·· Notched portion (notched portion of light guide)
63 .. Reflector (light guide case)
63a..Opening part 63b..Protrusion part 63c..Notch part (notch part of light guide)
64 .. Reflector (light guide case)
64a ·· Opening portion 64b ·· Protruding portion 64c ·· Chamfered portion (notch portion of light guide)

Claims (6)

A light-emitting element; a light-emitting element disposed at an end; and a rod-shaped light guide that propagates light from the light-emitting element incident on the inside while reflecting the light along the major axis direction; and A reflector that surrounds the light guide with a gap and is provided along the long axis direction, and is provided on the light guide side of the reflector and emits excited fluorescence by absorbing light from the light emitting element. An image reading line light source comprising a phosphor layer. The reflector has an opening formed with a long groove along the long axis direction while providing a predetermined gap with the light guide and surrounding the light guide, and each of the openings formed with the long groove 2. The image reading line according to claim 1, further comprising a narrow light reflection pattern provided in a line shape along the major axis direction on an outer peripheral surface of the light guide facing the end portion with a gap. light source. In the process in which the light from the light emitting element propagates through the light guide, the phosphor layer captures the light from the light emitting element emitted from the surface of the light guide and reflects the light from the light emitting element. And generating two or more kinds of composite light converted into light having an optical wavelength different from that of the light from the light emitting element, and transmitting the light generated in the phosphor layer through the inside of the light guide. The line light source for image reading according to claim 1, wherein the object to be irradiated is irradiated with the composite light including light from the light emitting element. In the process in which the light from the light emitting element propagates through the light guide, the phosphor layer scatters or specularly reflects the light from the light emitting element that is emitted from the surface of the light guide. Captures and reflects the light from the light emitting element and generates two or more kinds of composite light converted into light having an optical wavelength different from that of the light from the light emitting element, and the light generated by the phosphor layer The line light source for image reading according to claim 2, wherein the light source is irradiated with the composite light including the light from the light emitting element through the opening through the inside of the light guide. A rod-shaped light guide that propagates incident light incident on the inside from the end while reflecting along the long axis direction, and surrounds the light guide by providing a predetermined gap with the light guide along the long axis direction. And a phosphor layer that is provided on the light guide side of the reflector and that absorbs the incident light and emits excited fluorescence. The reflector has an opening formed with a long groove along the long axis direction while providing a predetermined gap with the light guide and surrounding the light guide, and each of the openings formed with the long groove The light guide unit according to claim 5, further comprising a narrow light reflection pattern provided in a line shape along the major axis direction on an outer peripheral surface of the light guide that is opposed to the end portion with a gap.

Images