CN101194498A - Image sensor and image read device - Google Patents

Abstract

The invention provides an image sensor and an image reading device. The image sensor does not require a significant increase of a substrate width even when a bar-shaped light source is arranged at both sides of a resin lens plate and having an excellent part positioning accuracy. The image sensor includes a bar-shaped light source for emitting light to an image to be read, an image formation optical system for collecting light reflected from the image to be read, and a light reception element for receiving light which has passed through the image formation optical system. The light reception element is arranged at a predetermined position of a substrate. The substrate has a through hole for receiving the terminal of a lead frame of the bar-shaped light source. The terminal of the lead frame of the bar-shaped light source is bent toward the center of the substrate and connected to the through hole.

Description

Imageing sensor and image read-out

Technical field

The present invention relates to imageing sensor and the image read-out that has this imageing sensor, particularly seek the miniaturization of imageing sensor substrate.

Again, the present invention can prevent from be equipped on the generation that becomes afterimage or fan's light of problem in the imaging optical system on the unit that optical system uses of reading that writes optical system or scanner etc. of optical printer etc. effectively.

Further, the present invention seeks the slit to the positional precision of optical axis and the favourable raising of reading the range accuracy of optical system and document board.

Background technology

The reading on the unit that optical system uses of optical system and scanner etc. that write at optical printer etc. carried imageing sensor.

The imageing sensor (contact image sensor) that connects airtight type, as shown in Figure 1, formation is made of bar-shaped light source 1, imaging optical system 2 and photo detector (line image transducer) 3, by bar-shaped light source 1 irradiation original copy (be also referred to as and be read image) 4, detect from the structure of the light of original copy 4 reflections by photo detector 3 via imaging optical system 2.In addition, the label among the figure 5 is substrates.

And, as above-mentioned imaging optical system 2, the tabular lens arra (with reference to patent documentation 1) of the rod-like lens array of the many distributed refractive index rod lens of use arrangement or flat sheet type micro-lens array etc.

Patent documentation 1: the spy opens the 2003-202411 communique

, in being equipped on the scanner of photocopier etc., also need books etc. are scanned, so be extensive use of the cold-cathode tube that directionality is low and brightness is high etc. of light usually.

But, because this cold-cathode tube use mercury etc. has the material of baneful influence to environment, so discussing the bar-shaped light source that is replaced into light sources such as LED.

Again, above-mentioned tabular lens arra is configured in sphere or aspheric micro lens on the flat board regularly with preset space length, can be with transparent resin etc. as the material of this lens arra.In such imaging optical system, importantly prevent to become afterimage or fan's light of the low reason of picture quality effectively.In order to prevent to become afterimage or fan's light of the low reason of picture quality, must make the unwanted light of imaging is not incided in the lens, therefore photomask is being set on lens surface.

But, only photomask being set on lens surface, can not prevent at the inner fan's light that takes place of lens.In order to prevent fan's light of lens inside, need photomask be set in lens inside, and not separating each lens, but when the integrally formed making lens arra by ejection formation etc., can not photomask be set in lens inside from the mode of the unwanted light of adjacent lenses incident.

In the contact image sensor that adopts the bar-shaped light source that uses led light source, usually, as shown in Figure 2, because bar-shaped light source only is configured in sub scanning direction one-sided of sensor element, adopt the short rod lens of focal length again, so when the original copy of scanning books etc., it is low and departed from the fuzzy etc. of the reading images that causes by the focus of lens by the float original copy illumination that causes of original copy to exist generation, makes the quality of reading images significantly worsen such problem.

Depart from the fuzzy of the reading images that causes for the focus by lens, as lens, the resin lens that lift-launch can access the longer degree of depth gets final product.

In order to prevent shade, can consider bar-shaped light source is arranged on the both sides of resin lens to the illumination of original copy again.

But, when bar-shaped light source is configured in the both sides of resin lens plate, cause substrate width to increase, the cost of parts is risen.

Promptly, as shown in Figure 3, in order to realize the electrical connection between bar-shaped light source 1 and the substrate 5, the through hole 7 of substrate 5 need be set on the terminal position as bar-shaped light source 1 and the lead frame 6 of the electrical connecting unit of substrate 5, but obviously will increase the width of substrate in order to dispose such through hole 7, the result exists and causes cost to increase such problem.Device is maximized again.In addition, in Fig. 3, dotted line represents to be arranged on the bar-shaped light source on the right side on the other end of substrate and the status of electrically connecting (as follows) of substrate.

, can to consider above lens that (from a side of the reverberation incident of original copy) is provided with the slit in order preventing, thereby to prevent afterimage or veiling glare at the inner veiling glare that takes place of lens again.

Usually, in order to be encased in easily in the imageing sensor, in the hood-like parts of shading, form the slit that daylighting is used.But, because in contact image sensor, light source is configured near the transducer optical axis, so exist the light path that light shield (hood) with the slit covers light source, interdicted a part of such problem to the illumination light of original copy.

That is, because the distance of light source and original copy is near more, the light quantity that shines original copy is big more, so light source need be configured near the transducer optical axis.When particularly using the tabular lens arra,,, this point is even more important so becoming because lens width increases as imaging optical system.

But, when on the position that light source is configured in the light quantity maximum in the original copy face, as shown in Figure 4, covered the part of irradiates light by light shield with the slit, reduced light quantity on the contrary.On the other hand, in the time of on light source being arranged on the position that irradiates light do not cover by light shield, because the distance of light source and original copy face, so the light quantity that exists on the original copy face still reduces, the quality of image reduces such problem.

Again, if promptly be subjected to the light precision not high in whole length of lens direction upper shed precision and straight line precision, then the slit can not prevent whole afterimages effectively.Again, exist when light generation irregular reference in peristome, afterimage takes place, the problem that image quality decline is such.

For example, when having the light shield in slit, because the weak strength of the own shape of maintenance of synthetic resin so worsened by the light precision, can not prevent on whole positions of length of lens direction that afterimage from taking place by the making such as ejection formation of resin.

Summary of the invention

The present invention can advantageously solve above-mentioned each problem, and its purpose is as follows.

1. disposed in the situation of bar-shaped light source even if provide, also can not cause the great increase of substrate width, again also very superior imageing sensor aspect the position component precision in the both sides of resin lens plate.

2., also light source can be configured near the transducer optical axis, thereby not reduce the contact image sensor of irradiation light quantity even if provide in the situation that is provided with the light shield in slit.

3. provide and used the image quality excellent contact imageing sensor that the intensity that keeps own shape is big, be subjected to the high light shield of having the slit of light precision.

4. provide by optical axis being disposed the slit, can more effectively prevent the imageing sensor of afterimage with high accuracy more.

5. the range accuracy that reads optical system and document board by raising is provided, can further improves the imageing sensor of image quality.

6. provide by the shell that will have the optical system of reading suitably to be erected in its frame pedestal, carry out the imageing sensor of its carrying and processing easily.

Again, the invention people have carried out conscientiously investigation repeatedly in order to solve above-mentioned problem, and the result obtains following opinion.

1. if the terminal of lead frame that makes bar-shaped light source then can dwindle substrate width to substrate center lateral bending song.

2., then dwindle substrate width, and carry out the location adjustment of parts easily if the terminal of the lead frame of bar-shaped light source is connected with through hole via electric conductor.

3. if utilize the raw material of metallic plate, then because can make component thickness thin, so correspondingly be difficult to interdict light from light source as the light shield parts.Further, if will make chamfer shape,, can not interdict light from light source even if then make light source more near original copy with the angle part of the light source side of the light shield in slit yet.

4. if make the light shield of having the slit, then, be subjected to the light precision again, so improved because keep the intensity height of own shape with metal.Particularly because in this light shield, when on whole length direction, being provided for improving the bend of intensity, can further improving and be subjected to the light precision.Further, form the slit by carry out Punching Technology from light incident side, can access die-cut section is trapezoidal peristome, and the result can prevent the irregular reference of light in gap opening portion.

5. in addition,, can prevent veiling glare (hot spot (flare)) effectively by suitable surface treatment is implemented in metal surface and the back side (the inside) of having the light shield in slit.

6. by the hole of location usefulness is set respectively, in this hole, insert the positioning pin nail in the light shield of having the slit and shell, both are fixed, can improve the positional precision of slit optical axis.In addition, when light source was arranged on the both sides of imaging optical system, extremely difficulty was guaranteed its positional precision in the past.

When with above-mentioned positioning pin nail fixing with the slit light shield and during shell, make positioning pin nail be provided with the position be in main scanning direction two ends above, and it is certain making the rising height from the slit face of this positioning pin nail, if and be provided for then to improve the range accuracy of optical system and document board extraordinarily with the light shield in slit by the compression spring that is pressed on the document board via this positioning pin nail.

8. when the outer casing frame that will have the optical system of reading is located in the frame pedestal, make shell be not easy the structure that comes off from frame pedestal, carry out its carrying and processing easily by formation.

The present invention is based on above-mentioned opinion.

That is, main idea structure of the present invention is as follows.

(1) a kind of imageing sensor, have the original copy of the mounting of light shining on document board bar-shaped light source, assemble from the imaging optical system of the light of this original copy reflection and the photo detector that the light of this imaging optical system has been passed through in acceptance, this photo detector is arranged on the precalculated position of substrate, and have the through hole of the terminal of the lead frame of accepting this bar-shaped light source in this substrate, this imageing sensor is characterised in that:

The terminal of lead frame that makes above-mentioned bar-shaped light source is to substrate center lateral bending song, thereby is connected with above-mentioned through hole.

(2) a kind of imageing sensor, have the original copy of the mounting of light shining on document board bar-shaped light source, assemble from the imaging optical system of the light of this original copy reflection and the photo detector that the light of this imaging optical system has been passed through in acceptance, this photo detector is arranged on the precalculated position of substrate, and have the through hole of the terminal of the lead frame of accepting this bar-shaped light source in this substrate, this imageing sensor is characterised in that:

The terminal of the lead frame of above-mentioned bar-shaped light source is connected with above-mentioned through hole via electric conductor.

(3) imageing sensor of record in above-mentioned (1) or (2) is characterized in that:

Between above-mentioned original copy and above-mentioned imaging optical system, the metallic light shield that thin thickness is set is as gathering via the slit from the light shield with the slit of the light of above-mentioned original copy reflection, with this metallic light shield, pack in the shell with the substrate that is provided with above-mentioned bar-shaped light source, above-mentioned imaging optical system and above-mentioned photo detector.

(4) imageing sensor of record in above-mentioned (3) is characterized in that:

On the main scanning direction two ends of above-mentioned metallic light shield and on the relevant position of above-mentioned shell the hole of locating usefulness is set respectively, in this hole, inserts the positioning pin nail, both are fixed;

Be provided for following closely above-mentioned shell by the compression spring that is pressed on the above-mentioned document board via this positioning pin;

On the main scanning direction side faces at both ends of above-mentioned shell, a pair of projection up and down is set, and on the both ends of the surface of the frame pedestal of built-in above-mentioned shell, the otch path that imports this projection is set.

(5) imageing sensor of record in above-mentioned (3) or (4) is characterized in that:

For above-mentioned light shield with the slit, the angle part of bar-shaped light source side is made chamfer shape.

(6) imageing sensor of putting down in writing in each of above-mentioned (3)～(5) is characterized in that:

With in the light shield in slit, on whole length direction, be provided for improving the bend of intensity above-mentioned.

(7) imageing sensor of putting down in writing in each of above-mentioned (3)～(6) is characterized in that:

Above-mentioned slit is to form by the Punching Technology from light incident side.

(8) imageing sensor of putting down in writing in each of above-mentioned (3)～(7) is characterized in that:

Above-mentioned with the slit light shield and above-mentioned shell on any, be provided for the jut of the location usefulness that both are chimeric, hole or recess with the chimeric location usefulness of this jut are set on another.

(9) imageing sensor of record in above-mentioned (8) is characterized in that:

Make be arranged on above-mentioned with the slit light shield or above-mentioned shell in the hole or recess of location usefulness on any bigger in the length of gap length direction in the length of gap length direction than the jut of above-mentioned location usefulness.

(10) imageing sensor of putting down in writing in each of above-mentioned (3)～(7) is characterized in that:

Above-mentioned bar-shaped light source is arranged on the both sides of above-mentioned imaging optical system.

(11) imageing sensor of record in above-mentioned (10) is characterized in that:

The above-mentioned shape of having the light shield in slit is made the lid shape, this lid shape with the light shield in slit and above-mentioned shell on any, be provided for the jut of the location usefulness that both are chimeric, hole or recess with the chimeric location usefulness of this jut are set on another.

(12) imageing sensor of putting down in writing in each of above-mentioned (3)～(11) is characterized in that:

The black application is implemented at the above-mentioned back side of having the light shield in slit handled, the opposing party's opposed face implements black application processing or the black chemical conversion is handled.

(13) imageing sensor of record in above-mentioned (12) is characterized in that:

Reflectivity In/Io (1/sr) during angle of reflection θ=0 ° is below 0.6, and the reflectivity In/Io during angle of reflection θ=50 ° is below 0.3.

(14) imageing sensor of putting down in writing in each of above-mentioned (3)～(13) is characterized in that:

On the slotted section of above-mentioned light shield with the slit, installed and be used to stop foreign particle to go into to invade transparent protective film in the light shield.

(15) imageing sensor of putting down in writing in each of above-mentioned (4)～(14) is characterized in that:

Above-mentioned otch path is made the compound path of curved path and vertical-path, on the top of this vertical-path, be provided with above-mentioned a pair of projection upper ledge keep out of the way the zone.

(16) a kind of image read-out is characterized in that:

Have the imageing sensor of putting down in writing in each of above-mentioned (1)～(15).

Effect of the present invention is as follows.

1. because the terminal of lead frame that makes bar-shaped light source to substrate center lateral bending song, is connected with the through hole of substrate, thus can realize the downsizing of substrate width, so that the miniaturization of device, the reduction of further cost.

2. because the terminal of the lead frame of bar-shaped light source is connected with through hole via electric conductor, so except dwindling substrate width, can also tackle the location adjustment of parts comfortablely.

3. because the metallic plate by utilizing thin thickness as the light shield (hereinafter referred to as the slit light shield) with the slit, can make component thickness thin, thus with the situation that forms the slit light shield with resin etc. relatively, be difficult to interdict light from light source.Again,, make to keep the intensity of own shape big, improved and be subjected to the light precision by making of metal.By on the length direction of whole light shield, being provided for improving the bend of intensity, improved this effect more.Further, make chamfer shape,, also can not interdict light from light source even if make light source more near original copy by angle part with the light source side of slit light shield.

4. because form the slit by Punching Technology, can access die-cut section is trapezoidal peristome, so can prevent the irregular reference of light in gap opening portion.

Bar-shaped light source only is being configured in the one-sided situation of imaging optical system, hole by will being arranged on the location usefulness in the light shield of slit and to be arranged on the jut of the location usefulness in the shell chimeric and assemble can easily be carried the slit light shield on shell accurately.At this moment, because the length of gap length direction in the hole by making location usefulness is bigger than the length of the gap length direction of jut, can absorb thermal coefficient of expansion poor of resinous shell and metallic light shield, so further improved precision.

In the situation of the both sides that bar-shaped light source are configured in imaging optical system, make the lid shape by shape with the slit light shield, in any of the slit of this lid shape light shield and shell, projection is set, recess is set in another, by they are chimeric, can accurately the slit light shield be carried on shell.

5. by the hole of location usefulness is set respectively, in this hole, insert the positioning pin nail on slit light shield and shell, both are fixed, can improve the positional precision of slit optical axis.

In addition, by with the both sides that bar-shaped light source are configured in imaging optical system, with the shape of slit light shield make the lid shape, in any of the slit of this lid shape light shield and shell, jut be set, hole or recess be set in another, structure that they are chimeric is compound, can improve this effect more.

6. when with positioning pin nail fixedly when slit light shield and shell, by make positioning pin nail be provided with the position be in main scanning direction two ends above, it is certain making the rising height from the slit face of this positioning pin nail, and with the compression spring via positioning pin nail with the slit light shield by being pressed on the document board, can improve the range accuracy of optical system and document board extraordinarily.

7. when the outer casing frame that will have the optical system of reading is located in the frame pedestal, make shell be not easy the structure that comes off from frame pedestal, can improve the easiness of its carrying and processing significantly by formation.

Description of drawings

Fig. 1 is the schematic diagram of general imageing sensor.

Fig. 2 is the schematic diagram with the imageing sensor of bar-shaped light source.

Fig. 3 is the schematic diagram that has the imageing sensor of bar-shaped light source in resin lens plate both sides.

Fig. 4 is the profile of contact image sensor in the past.

Fig. 5 has in the imageing sensor of bar-shaped light source in resin lens plate both sides, according to the present invention, makes the schematic diagram of the terminal of lead frame to the imageing sensor of substrate center lateral bending song.

Fig. 6 is only in the one-sided imageing sensor that has a bar-shaped light source of resin lens plate, according to the present invention, makes the schematic diagram of the terminal of lead frame to the imageing sensor of photo detector lateral bending song.

Fig. 7 is the oblique view at the back side of the general imageing sensor of expression.

Fig. 8 represents according to the present invention, makes the oblique view of the substrate width state shorter than the portion of terminal of lead frame.

Fig. 9 be expression according to the present invention, make the oblique view of the state that lead terminal and through hole couple together via flexible printed circuit board.

Figure 10 is the schematic diagram that the expression optical axis is adjusted main points.

Figure 11 is the profile according to preferred contact image sensor of the present invention.

Figure 12 is the profile according to contact image sensor of the present invention that the angle part of the bar-shaped light source side of slit light shield is made chamfer shape.

Figure 13 is the figure that is illustrated in the bend that forms in the chamfered section of slit light shield.

Figure 14 is the figure of expression according to preferred slit of the present invention section shape.

Figure 15 is the figure that represents slit section shape in the past.

Figure 16 makes the section shape in slit become the key diagram of the method for trapezoidal cross-section by Punching Technology.

Figure 17 is the figure of the chimeric main points of slit light shield when being illustrated in the bar-shaped light source of 1 of one-sided of tabular lens arra configuration and shell.

Figure 18 is the figure of assembling main points that expression can absorb the coefficient of thermal expansion differences of slit light shield and shell.

Figure 19 is that expression is with bar-shaped light source, tabular lens arra, the substrate of having photo detector and the exploded perspective view that the slit light shield is encased in the main points in the shell.

Figure 20 is when disposing bar-shaped light source in tabular lens arra both sides, according to the profile of preferred contact image sensor of the present invention.

Figure 21 is when disposing bar-shaped light source in tabular lens arra both sides, according to the profile of preferred contact image sensor of the present invention (with transparent protective film).

Figure 22 is the figure that expression is installed to transparent protective film the main points of slit portion.

Figure 23 is the figure of the chimeric main points of the slit light shield of expression when the slit light shield is made the lid shape and shell.

Figure 24 is hot spot (veiling glare) generating capacity when more respectively various surface treatment is implemented at the surface of metal light shield with the slit and the back side and the chart of expression.

Figure 25 is that expression has been implemented identical surface-treated metallic light shield to the surface with back side both sides and do not implemented the curve chart of surface reflection situation of the metallic light shield of any processing.

Figure 26 is the figure of the mensuration main points of presentation surface reflection.

Figure 27 is illustrated in the oblique view that inserts the positioning pin nail in the hole of the location usefulness that is arranged at respectively in slit light shield and the shell and make the state that both fix.

Figure 28 is illustrated in the profile that inserts the positioning pin nail in the hole of the location usefulness that is arranged at respectively in slit light shield and the shell and make the state that both fix.

Figure 29 be expression with compress spring with the slit light shield by the figure that is pressed in the state on the document board.

The figure in Figure 30 otch path that to be expression be made of the compound path of curved path and vertical-path.

(description of reference numerals)

1 bar-shaped light source

2 imaging optical systems

3 photo detectors

4 are read image (original copy)

5 substrates

6 lead frames

7 through holes

8 electric conductors

101 bar-shaped light sources

102 imaging optical systems (tabular lens arra)

103 photo detectors (line image transducer)

104 are read image (original copy)

105 substrates

106 slits

107 slit light shields

108 document boards (glass plate)

109 shells

110 chamfered section

111 bends

112 puncheres

113 moulds

114 location juts

The hole is used in 115 location

206 slits

207 slit light shields

209 shells

212 transparent protective films

The hole is used in 214 location that are arranged in the metallic light shield

The hole is used in 215 location that are arranged in the shell

216 positioning pins nail

217 compression springs

218 projections

219 frame pedestals

220 otch paths

Embodiment

Below, specifically describe the present invention.

(A) at first, the situation that realizes the miniaturization of imageing sensor substrate is described.

At this moment, as shown in Figure 5, change the terminal shape of the lead frame 6 of bar-shaped light source 1 again.

That is, the terminal of the lead frame 6 by making bar-shaped light source 1 makes the position of the through hole 7 in the substrate 5 move to middle body to substrate center side (centerline side) bending, and the through hole position of substrate 5 is positioned near the substantial middle of substrate 5.

According to said structure,, can realize the downsizing of substrate width as from can see with the comparison of Fig. 3.

More than, the situation that has disposed bar-shaped light source in the both sides of resin lens plate has been described, but the present invention not only is defined in this, even if only in the one-sided configuration of resin lens plate in the situation of bar-shaped light source, also can access same effect.

Promptly, as shown in Figure 6, in the one-sided configuration of resin lens plate in the situation of bar-shaped light source, the terminal of the lead frame 6 by making bar-shaped light source 1 is to photo detector 3 lateral bending songs, the position that can make the through hole 7 in the substrate 5 is than more moved to photo detector 3 sides in the past, therefore, can realize the downsizing of substrate width.

Secondly, in Fig. 7, represent the back side of contact image sensor with oblique view.

, as shown in the figure, the terminal of lead frame 6 was inserted in the through hole 7 of substrate 5 welding through hole portion in this state and realize being electrically connected in the past.

Relative therewith, in the present invention, as shown in Figure 8, it is shorter than the portion of terminal of lead frame 6 to form the width that makes substrate 5, as shown in Figure 9, realizes the structure of the electrical connection between through hole 7 and the lead terminal via electric conductor 8.

Here, as electric conductor, flexible printed circuit board is to be fit to and favourable, but also can engage by other lead-in wire etc.

According to this structure, the width of substrate is not subjected to the restriction of the terminal position of lead frame, can make it have suitable width.

In addition, in the optical system in needs configuration slit,, require high precision about the location of gap opening portion with the sub scanning direction that is subjected to the optical sensor row.Therefore, in contact image sensor, after the assembling,, as shown in figure 10, need realize the optical axis adjustment by substrate is moved with respect to shell in order to realize the position adjustment of gap opening and sensor column.

Therefore, the terminal of the lead frame of bar-shaped light source changes the possibility that the terminal of generation lead frame can not enter through hole with the position relation that is arranged on the through hole in the substrate.

But, as the present invention, when carrying out the electrical connection of lead terminal and through hole, can tackle such optical axis adjustment via other parts.

Again,, preferably use the value material about equally of each thermal coefficient of expansion, therefore, can prevent effectively by the particularly deterioration of the positional precision that causes of variations in temperature of environmental change as the raw material of shell and substrate.

In addition, preferably making giving of substrate surface and substrate close (bonding) is black, therefore, can help preventing veiling glare.

Further, preferably make the middle body of the allocation position of photo detector at substrate.So say so because when the lateral edges with the close substrate of photo detector disposes, because the annealing in process when being bonded in photo detector on the substrate causes the bimetallic phenomenon, be created in the possibility that deforms in the substrate and positional precision is worsened, in contrast, when photo detector being configured in the middle body of substrate, just do not have such possibility, can improve the cause of installation accuracy.

(B) secondly, the situation that prevents in the generation that writes reading of optical system or scanner etc. become problem in the imaging optical system on the unit that optical system uses afterimage or veiling glare that is equipped on optical printer etc. is described.

Figure 11 represents according to preferred image transducer of the present invention, in Figure 11, because the backbone of structure is identical with the Fig. 4 that discloses previously, so additional identical label is represented, label 106 among the figure is the slits of gathering from the light of original copy reflection, the 107th, have the metal light shield in this slit 106.As the raw-material metal of this light shield, iron or steel etc. is best suited for, even if but if metal then nonferrous metal also it doesn't matter, this is self-evident.And, the 108th, be used for the document board (glass plate) of mounting original copy, the 109th, shell.

The imageing sensor relevant with the present invention, as shown in figure 11, formation will make the bar-shaped light source 101 of rayed on original copy 104, gather pack into the structure of shell 109 of the substrate 105 of photo detector 103 of accepting to have passed through the light of this tabular lens arra 102 to original copy 104 irradiations and the tabular lens arra 102 and having of imaging optical system that passed through the light in this slit 106 at the slit light shield 107 of the light of original copy reflection or transparent copy, as convergence from this bar-shaped light source 101 via slit 106.

As shown in figure 11, the illumination of penetrating from lighting device (bar-shaped light source) 101 is mapped to the roughly in the localities same of the original copy 104 that is arranged on the glass plate 108.In addition, both can form the one-sided structure that 1 lighting device only is configured in the tabular lens arra as shown in figure 11, also can form the structure that like that 2 lighting devices is configured in both sides as described later.

Slit 106 is arranged on peristome and transducer optical axis roughly on the consistent location again.In addition, in order to adjust the interval of slit light shield 107 and glass plate 108, also can between slit light shield 107 and glass plate 108, insert pad (not shown).

Again, in the present invention, as mentioned above, because make slit light shield 107, so can reduce thickness significantly with in the past resinous situation comparison with metal.Thereby, in the situation of the allocation position that makes bar-shaped light source 101 and in the past identical (identical), reduced the ratio of the illumination light that covers by this slit light shield 107 significantly with Fig. 4.As a result, can improve image quality.

; as as seen from Figure 11; because when making slit light shield 107 with metal, compare with the situation of making of resin according to the present invention; can reduce thickness significantly, so can make correspondingly proximity transducer optical axis of bar-shaped light source 101 and the amount that can reduce slit light shield 107 thickness.

But, when making bar-shaped light source 101 simply during the proximity transducer optical axis, still cover a part of irradiates light by slit light shield 107, make light quantity reduce therewith amount accordingly.

Therefore, in the present invention, even if to make bar-shaped light source 101 proximity transducer optical axises, slit light shield 107 does not cover the mode of irradiates light yet, as shown in figure 12, the angle part of the bar-shaped light source side of slit light shield 107 is made chamfer shape.

By such structure, guarantee the light path of light source, irradiates light is not covered by slit light shield 107 and, light quantity can be increased significantly all towards original copy 104.Among the figure, label 110 is chamfered section.

Again, in the present invention, in order further to improve the intensity of slit light shield 107, the opening precision and the straight line precision that improve on whole length of lens direction promptly are subjected to the light precision, also can on its whole length direction bend be set in slit light shield 107.

In the mode of the light inlet light path of the light path that do not hinder bar-shaped light source and resin lens plate, as shown in figure 13, it is favourable forming this bend in the chamfered section 110 of the angle part of the bar-shaped light source side that is arranged at slit light shield 107.Among the figure, label 111 is bends.

In the present invention, about the setting angle of lighting device (bar-shaped light source), when when the exit facet of establishing glass plate and lighting device is parallel, being 0 °, than 0 ° big and be preferred below 45 °.This be because when 0 ° by glass plate total reflection illumination light, the height dimension change that not only makes imageing sensor again when surpassing 45 ° and makes the cause of luminous intensity distribution deterioration greatly.

As above-mentioned lighting device, for example to be contained in the resin box of white be to be fit to and favourable to the bar-shaped light guide that will be made of the transparent resin of propylene etc.Luminescence unit is installed at least one end of resin box,, light is penetrated from the outgoing plane of bar-shaped light guide, be radiated on the above-mentioned original copy at the light of bar-shaped light guide inner total reflection from this luminescence unit.

As the tabular lens arra, preferably by at least 2 spheres or aspheric micro lens are configured in resin lens plate on the flat board regularly with preset space length, so that the mode of the optical axis unanimity of each micro lens overlaps the upright lens arra of resin that gets up to form.

Can make such resin lens plate by ejection formation.The resin lens plate of making of ejection formation has long oblong-shaped, the lens that are formed on middle body form in the zone, along length direction (main scanning direction that is equivalent to imageing sensor) the many spheres of configuration or the aspheric micro lens of resin lens plate, edge and direction (sub scanning direction) the configuration multiple row sphere of length direction quadrature or the structure of aspheric micro lens.

This resin lens plate because the depth of focus is darker, is difficult to take place floated that the original copy illumination that causes reduces or departed from the fuzzy etc. of the reading images that causes, the high such advantage of the quality of reading images by the focus of lens by original copy so also have.

Chimeric by being arranged on lens board depressed part on every side with the jut that is arranged in the shell, this lens board is contained in the shell.By cover with shell lens board around, can cover the imaging to picture point the light that incides lens from original copy not have light or the external scattered light contributed.It is preferred that the inwall of shell is implemented the light absorption processing.

The width that is arranged on the slit in the light shield is equated or narrower than it with the width of the sub scanning direction in the zone (lens form the zone) of the formation lens of lens board.

The slit light shield if metal then there is no particular limitation, but is particularly suitable with the high steel plate making of rigidity.

Here, the section shape in slit, as shown in figure 14, forming the peristome area is favourable at light incident side (incident is from a catoptrical side of original copy) than little trapezoidal of lens side.And, make tiltangle in this trapezoidal cross-section for identical with the angle of visual field of lens arra or be preferred than its big angle.Say so be because when tiltangle than the angle of visual field hour, as shown in figure 15,, become the reason that afterimage takes place at the sidewall sections reverberation of peristome.

In addition, the angle of visual field is an angle described below.

From the light of 1 outgoing of original copy, in the lenticule arbitrarily on inciding the multilayer lens arra after, incide on the photosensor array with 1 of original copy corresponding pixel on.To incide in the light of this photosensor array, the tilt angle of maximum light of lens axis is called the angle of visual field.

Slit with such trapezoidal cross-section shape as shown in figure 16, can form by Punching Technology.At this moment, as shown, gap (clearance) by making puncher 112 and mould 113 is big, is carried out die-cutly from the light incident side (incident is from a catoptrical side of original copy) in slit by puncher, and the section shape that can suitably adjust the slit is the tiltangle in the trapezoidal cross-section.

Below, the slit light shield when only 1 bar-shaped light source being configured in tabular lens arra one-sided and the assembling of shell are described.

At this moment, both assemblings are by for example as shown in figure 17, and the jut (being also referred to as protuberance) 114 that makes the location usefulness that is arranged in the shell 109 and the hole that is arranged on the location usefulness in the slit light shield 107 115 be chimeric carries out.Be convex then there is no particular limitation if be arranged on the shape of the pin 114 of the location usefulness in the shell 109.Being arranged on the hole 115 in the slit light shield 107, both can be through hole, also can make recess.Again, on the contrary, also can hole or recess be set in shell 109, in slit light shield 107, jut be set.

Again, the jut 114 of location usefulness is circular, and the hole 115 of slit light shield 107 is preferred for long hole shape.Amount to 2 if 1 such hole is set in each end at least, then can assemble, but when making 2 holes all be long hole shape, can not guarantee the positional precision of length direction.Therefore, as shown in figure 18, if respectively be provided with 1 in the end at least, be provided with 1 in central authorities, 3 holes are set altogether (in Figure 18, are illustrated in the end and respectively are provided with 2, be provided with 1 in central authorities, the situation in 5 holes is set altogether), making the hole of central authorities is circular hole, makes the hole of end be respectively slotted hole, then can in the circular hole of central authorities part, guarantee positional precision, partially absorb the poor of thermal coefficient of expansion by the slotted hole of end.Again, because,,, also can select quadrangle etc. so the shape of hole or recess is not limited to ellipse so long as the length of the length direction of hole or the recess shape bigger than the length of the length direction of jut gets final product in order to absorb coefficient of thermal expansion differences.

In addition, so the slit light shield is a conductor because of being formed by metallic plate, but also can further form conductive film from the teeth outwards.If can adjust current potential as the metallic plate of conductor or above-mentioned conductive film, then keep idiostatic with photoreceptor by adjusting current potential, can prevent from toner is attracted to come, prevent toner attached on the lens board, be preferred therefore.

For reference, in Figure 19, represent the exploded view of the assembling main points of bar-shaped light source 101, tabular lens arra 102, the substrate 105 of having photo detector 103 and 107 pairs of shells 109 of slit light shield with oblique view.

Below, the situation that bar-shaped light source is configured in tabular lens arra both sides respectively is described.

At this moment, consider bar-shaped light source to be configured in tabular lens arra both sides, the slit light shield need be made the lid shape.And the angle part that makes bar-shaped light source side is that to make chamfer shape be preferred to two shoulders of lid.Be more preferably, as shown in figure 20, the bend 111 that will be used to improve intensity is arranged on chamfered section 110 on whole length direction.

Again, at this moment, because need dispose the slit 106 that is arranged in the slit light shield 107 accurately to optical axis, thus the preferred step that can position the slit that in shell 109, is provided with, the precision of the chimeric raising gap position by both sides.

Because by this structure, can be from tabular lens arra both sides irradiates light, so with only bar-shaped light source is configured in the one-sided situation of tabular lens arra relatively, can make the light quantity multiplication.

In the present invention,, as shown in figure 21, also the such transparent protective film 212 of hyaline membrane can be installed in the portion of slit for the foreign particle that stops dust etc. intrudes in the light shield of slit again.

When such hyaline membrane is installed, as shown in figure 21, both can paste from the outside of light shield, also can shown in Figure 22 (a), paste again from the inboard of light shield.Further, also can be shown in Figure 22 (b), directly at slit portion filling transparent resin.

Here, as the raw material of transparent protective film 212, if the high material of light transmittance can be any material then, there is no particular limitation, but allyl resin etc. are particularly suitable for and are favourable.

In addition, for the slit light shield 107 with such lid shape is encased in the shell 109, as shown in figure 23, for example in shell 109, several places are set and are used for chimeric both jut 114 of location usefulness along the length direction of slit light shield 107, on the other hand, hole with the chimeric location usefulness of this jut 114 is set in slit light shield 107, both are chimeric just.Such jut and hole also can be configured on the contrary with above-mentioned, and this is self-evident.

According to this structure, can improve the installation exercise of slit light shield and shell, reduce cost.

Below, surface and the suitable surface-treated situation of back side enforcement to the light shield of having the slit are described.

Figure 24 represent about respectively to metal (iron) system with the surface (original copy side) of the light shield in slit and all surface treatments of the back side (lens side) enforcement the time the result that investigates of hot spot (veiling glare) generating capacity.

Experiment is by after all surface treatments are implemented at the surface of metallic light shield and the back side, from light source irradiation redness (R), green (G) or blue (B) light, takes place about mensuration of all kinds that the hot spot of which kind of degree carries out.

" application " of the transverse axis of Figure 24 is that blacking is sprayed onto lip-deep processing.In this experiment, carry out application with the ヒ ノ Block ラ Star Network of industrial society of big Hino system.Surface after the application is the pears skin shape with roughness to a certain degree.Again, " chemical conversion " be by with metal impregnation in medicament, make surface oxidation and implement the processing of blackization.Surface after the chemical conversion is the pears skin shape with roughness to a certain degree.Further, " zinc-plated " is to implement zinc-plated to the surface of metallic light shield.Metal surface behind the plating is roughly level and smooth, presents black.

As shown in figure 24, see that the hot spot generating capacity is minimum when surface and back side both sides having been implemented application handle, secondly be when the surface has been implemented the chemical conversion processing, the hot spot generating capacity was low when the application processing had been implemented at the back side.

To this, when the surface has been implemented the application processing, when the back side has been implemented chemical conversion and has been handled, the hot spot generating capacity of R is many.This means that the reason that hot spot takes place mainly is to be caused by the reflection on the metallic light shield back side.Thereby, see that the reflecting properties specific surface that improves the back side is favourable.

Again, level and smooth when zinc-plated when surface and the back side are carried out, at R, G, all middle hot spot amounts of B are many.In addition, though do not disclose in Figure 24, the hot spot quantitative change got more when the chemical conversion processing had all been implemented at surperficial and the back side.

From Figure 24, hot spot amount minimum when the application processing has all been implemented at surperficial and the back side is superior as can be known.But because application processing cost height, so be preferred in order to suppress cost " back side implements that application is handled, surface implement chemical conversion and handle ".

Figure 25 measures the surface has been implemented identical surface-treated metallic light shield with back side both sides and do not implemented the result of surface reflection of the metallic light shield of any processing.

When carrying out this mensuration, as shown in figure 26,, transducer is set in position from the angle of reflection θ of lens from original copy lateral lenses irradiating laser, decide reverberation with the power instrumentation.Laser uses the He-Ne laser of 633nm, output: 5mW, and power meter (transducer) uses the Q8230 of 7 De バ Application チ ス ト society systems.

In Figure 25 the longitudinal axis of expression reflectivity be (In/Io)/solid angle (unit: 1/sr), with the ratio of reflection measurement value and laser output divided by solid angle.Here, In represents reflection measurement value (with the catoptrical value of fixed each angle of power instrumentation), and Io represents laser output (directly measuring the value of laser with power meter).

Again, solid angle can be tried to achieve as follows.When the light accepting part of establishing transducer divides area is A, and when the distance of dividing from laser irradiating position (reflection position) to the transducer light accepting part was r, solid angle was by A/4 π r ²(unit: sr (steradian)) expression.

Again, " (1) is handled in application " shown in Figure 25 is that the sample that application is handled has all been implemented at the surface and the back side of metallic light shield." (2) are handled in application " is same with " (1) is handled in application ", but is the diverse sample of coating, and the roughness on surface is bigger.

" chemical conversion is handled (1) " is that the sample that chemical conversion is handled has all been implemented on the surface of metallic light shield and the back side, and the surface after the processing is a grey.On the other hand, " chemical conversion is handled (2) " is same with " chemical conversion is handled (1) ", but is so-called dye black handle (having produced iron oxide from the teeth outwards), and the surface is a black.

In addition, " not having to handle " is the metallic light shield of not implementing any processing.

As shown in figure 25, reverberation is minimum be make surface roughening application handle ((2) are handled in application).The reverberation of having implemented the light shield of application processing or chemical conversion processing as can be known lacks than the light shield that does not have to handle.Particularly, when angle of reflection θ is big, do not have the reverberation of the light shield handled many, become the reason of image degradation.

From Figure 25 as seen, the reflectivity In/Io (1/sr) when angle of reflection θ=0 ° the time is below 0.6, and the reflectivity In/Io in the time of angle of reflection 0=50 ° we can say that reflecting properties is good in the situation below 0.3.

(C) below, illustrate to help improving the positional precision and the situation that read the range accuracy of optical system and document board of slit to optical axis.

At this moment, the metallic plate of using thin thickness is as the slit light shield, and is identical with the situation of above-mentioned (B).

And, at this moment, further,, in this hole, insert the positioning pin nail in the light shield of having the slit and shell by the hole of location usefulness is set respectively, both are fixed, can improve the positional precision of slit to optical axis.

Again, when with above-mentioned positioning pin nail fixing with the slit light shield and during shell, by make positioning pin nail be provided with the position be in main scanning direction two ends above, it is certain making the rising height from the slit face of this positioning pin nail simultaneously, and be provided for to improve the range accuracy of optical system and document board with the light shield in slit by the compression spring that is pressed on the document board via this positioning pin nail.In addition, use glass usually, but not only be defined in this as document board, any if the transparent body of plastics etc. then can use.

Further, when the outer casing frame that will have the optical system of reading is located in the frame pedestal, make shell be not easy the structure that comes off from frame pedestal, carry out its carrying and processing easily by formation.

Below, the situation that will dispose bar-shaped light source respectively in the both sides of tabular lens arra illustrates the assembling of slit light shield and shell as typical example.

At this moment, both assemblings for example as Figure 27 and shown in Figure 28, are provided with the hole of locating usefulness respectively on the main scanning direction two ends of slit light shield 207 and on the relevant position of shell 209, insert the positioning pin nail in this hole, and both are fixed.Among the figure, label 214 is arranged on the hole of the location usefulness in the metallic light shield, and 215 are arranged on the hole of the location usefulness in the shell, and 216 is positioning pin nails.

Like this, use hole 214,215 by the location that same diameter is set respectively in slit light shield 207 and shell 209, in these holes 214,215, insert positioning pin nail 216, both are fixed, can be to the positional precision of any one the raising slit in main scanning direction and the sub scanning direction to optical axis.

In addition, by being arranged on as in any of the relevant position of the bottom of the slit light shield as shown in Figure 23, the lid shape that discloses previously or shell, will locate that the hole of usefulness or recess are arranged in another, structure that they are chimeric is compound equally, further improve this effect with the jut that will locate usefulness.

Again, as described above, by the projecting height from the slit face that forms except the top positioning pin nail 216 that makes the main scanning direction two ends that are inserted in slit light shield 207 and shell 209 respectively is the certain height, as shown in figure 29, with the compression spring 217 with slit light shield 207 by the structure that is pressed on the document board 108, the distance that can always keep optical system and document board improves both range accuracies extraordinarily for certain.

Therefore, as shown, it is preferred making the head of positioning pin nail 216 become tabular surface.

Again, as the raw material of this positioning pin nail 216, UPE (ultra high molecular polyethylene), PEEK (polyether-ether-ketone) that mar proof and sliding are superior and MC nylon etc. are suitable and favourable.

Here, in the present invention, as mentioned above, follow closely the slit light shield by the structure that is pressed on the document board via positioning pin because form with the compression spring, so as shown in Figure 29, on the main scanning direction side faces at both ends of shell 209, a pair of projection 218 up and down is set, and on the both ends of the surface of the frame pedestal 219 of built-in shell 209, it is integral that the otch path 220 that imports such projection 218 is set.

But, in structure shown in Figure 29, exist because 220 in otch path is made of vertical-path, thus when when carrying or when handling by the reaction force that compresses spring 217, the possibility that shell 209 is come off from frame pedestal 219.

Therefore, in order to eliminate such possibility, as shown in figure 30, otch path 220 is made the compound path of curved path 220-a and vertical-path 220-b, on the top of this vertical-path 220-b, the upper ledge of a pair of projection 218 has kept out of the way regional 220-c just about being provided with.

If form this structure, then i.e. box lunch carrying or and when handling, the possibility that does not also have shell 209 to come off from frame pedestal 219.Again, when installing because the reaction force of compression spring 217, can be with suitable pressure with slit light shield 207 by being pressed on the document board 108.

And, by imageing sensor as described above is carried on image read-out, can access small-sized and be subjected to the high image read-out of light precision.

Claims (16)

1. imageing sensor, have the original copy of the mounting of light shining on document board bar-shaped light source, assemble from the imaging optical system of the light of this original copy reflection and the photo detector that the light of this imaging optical system has been passed through in acceptance, this photo detector is arranged on the precalculated position of substrate, and have the through hole of the terminal of the lead frame of accepting this bar-shaped light source in this substrate, this imageing sensor is characterised in that:

The terminal of lead frame that makes above-mentioned bar-shaped light source is to substrate center lateral bending song, thereby is connected with above-mentioned through hole.

2. imageing sensor, have the original copy of the mounting of light shining on document board bar-shaped light source, assemble from the imaging optical system of the light of this original copy reflection and the photo detector that the light of this imaging optical system has been passed through in acceptance, this photo detector is arranged on the precalculated position of substrate, and have the through hole of the terminal of the lead frame of accepting this bar-shaped light source in this substrate, this imageing sensor is characterised in that:

The terminal of the lead frame of above-mentioned bar-shaped light source is connected with above-mentioned through hole via electric conductor.

3. imageing sensor according to claim 1 and 2 is characterized in that:

Between above-mentioned original copy and above-mentioned imaging optical system, the metallic light shield that thin thickness is set is as gathering via the slit from the light shield with the slit of the light of above-mentioned original copy reflection, with this metallic light shield, pack in the shell with the substrate that is provided with above-mentioned bar-shaped light source, above-mentioned imaging optical system and above-mentioned photo detector.

4. imageing sensor according to claim 3 is characterized in that:

On the main scanning direction two ends of above-mentioned metallic light shield and on the relevant position of above-mentioned shell the hole of locating usefulness is set respectively, in this hole, inserts the positioning pin nail, both are fixed;

Be provided for following closely above-mentioned shell by the compression spring that is pressed on the above-mentioned document board via this positioning pin;

On the main scanning direction side faces at both ends of above-mentioned shell, a pair of projection up and down is set, and on the both ends of the surface of the frame pedestal of built-in above-mentioned shell, the otch path that imports this projection is set.

5. according to claim 3 or 4 described imageing sensors, it is characterized in that:

The angle part of the bar-shaped light source side of above-mentioned light shield with the slit is made chamfer shape.

6. according to each described imageing sensor in the claim 3～5, it is characterized in that:

With in the light shield in slit, on whole length direction, be provided for improving the bend of intensity above-mentioned.

7. according to each described imageing sensor in the claim 3～6, it is characterized in that:

Above-mentioned slit is to form by the Punching Technology from light incident side.

8. according to each described imageing sensor in the claim 3～7, it is characterized in that:

On above-mentioned light shield and in the above-mentioned shell any with the slit, be provided for the jut of the location usefulness that both are chimeric, hole or recess with the chimeric location usefulness of this jut are set on another.

9. imageing sensor according to claim 8 is characterized in that:

Make be arranged on above-mentioned with the slit light shield or the hole of the location usefulness in the above-mentioned shell any or recess in the length of gap length direction greater than the jut of above-mentioned location usefulness length in the gap length direction.

10. according to each described imageing sensor in the claim 3～7, it is characterized in that:

Above-mentioned bar-shaped light source is arranged on the both sides of above-mentioned imaging optical system.

11. imageing sensor according to claim 10 is characterized in that:

The above-mentioned shape of having the light shield in slit is made the lid shape, this lid shape with the light shield in slit and in the above-mentioned shell any on, be provided for the jut of the location usefulness that both are chimeric, hole or recess with the chimeric location usefulness of this jut are set on another.

12., it is characterized in that according to each described imageing sensor in the claim 3～11:

The black application is implemented at the above-mentioned back side of having the light shield in slit handled, the opposing party's opposed face implements black application processing or the black chemical conversion is handled.

13. imageing sensor according to claim 12 is characterized in that:

Reflectivity In/Io (1/sr) during angle of reflection θ=0 ° is below 0.6, and the reflectivity In/Io during angle of reflection θ=50 ° is below 0.3.

14., it is characterized in that according to each described imageing sensor in the claim 3～13:

On the slotted section of above-mentioned light shield with the slit, installed and be used to stop foreign particle to go into to invade transparent protective film in the light shield.

15., it is characterized in that according to each described imageing sensor in the claim 4～14:

Above-mentioned otch path is made the compound path of curved path and vertical-path, on the top of this vertical-path, be provided with above-mentioned a pair of projection upper ledge keep out of the way the zone.

16. an image read-out is characterized in that:

Have each described imageing sensor in the claim 1～15.

Images