Peltier module

Abstract

To improve productivity.SOLUTION: A peltier module 10 comprises: a pair of substrates that is arranged so as to face each other; a plurality of thermionic elements that is arranged between the pair of substrates; and an electrode that connects each thermionic element. One substrate of the pair of substrates includes a length difference in at least one direction to the other substrate.SELECTED DRAWING: Figure 2

Description

Technical Field

[0001] The present disclosure relates to a Peltier module.

Background Art

[0002] Techniques related to a Peltier module are known, which includes a pair of substrates arranged facing each other, a plurality of thermoelectric elements arranged between the pair of substrates, and electrodes connecting the thermoelectric elements (see, for example, Patent Document 1).

Prior Art Documents

Patent Documents

[0003]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0004] A Peltier module is used for temperature control of an optical communication device. With the increasing capacity of optical communication, miniaturization of the optical communication device is strongly required. To miniaturize the optical communication device, it is necessary to miniaturize the case. When assembling a Peltier module in which the upper and lower substrates have the same shape and the lengths of each side are aligned, the other substrate is bonded so that its end face matches that of one substrate. However, depending on the accuracy of the device used for bonding and the skill of the operator, the position may shift, and there is a risk that the upper and lower substrates will be bonded together with a misalignment. In this case, the outer shape of the Peltier module will increase by the amount of the misalignment. Therefore, the space for mounting the Peltier module in the container storing the Peltier module needs to be designed large considering the misalignment of the upper and lower substrates, resulting in an increase in the size of the container.

[0005] Also, in order to reduce the misalignment between the upper and lower substrates, methods such as bonding the substrates while fixing them with a positioning jig or the like can be considered, but the device and procedures become complicated, and there is a risk of reduced productivity.

[0006] This disclosure aims to improve productivity. [Means for solving the problem]

[0007] A Peltier module is provided, comprising a pair of substrates arranged opposite each other, a plurality of thermoelectric elements disposed between the pair of substrates, and electrodes connecting the thermoelectric elements, wherein one of the substrates has a length difference from the other substrate in at least one direction. [Effects of the Invention]

[0008] According to this disclosure, productivity can be improved. [Brief explanation of the drawing]

[0009] [Figure 1] Figure 1 is a schematic plan view showing an optical communication device according to the first embodiment. [Figure 2] Figure 2 is a schematic cross-sectional view showing an optical communication device according to the first embodiment. [Figure 3] Figure 3 is a schematic plan view of the first substrate of the Peltier module according to the first embodiment, and is a view from above. [Figure 4] Figure 4 is a schematic plan view of the second substrate of the Peltier module according to the first embodiment, and is a view from below. [Figure 5] Figure 5 is a schematic plan view showing the first and second substrates of the Peltier module according to the first embodiment. [Figure 6] Figure 6 is a schematic cross-sectional view showing the first and second substrates of the Peltier module according to the first embodiment. [Figure 7] Figure 7 is a schematic plan view showing the first and second substrates of the Peltier module according to the first embodiment. [Figure 8] Figure 8 is a schematic cross-sectional view showing the first and second substrates of the Peltier module according to the first embodiment. [Figure 9]FIG. 9 is a plan view schematically showing a first substrate and a second substrate of a Peltier module according to Modification 1. [Figure 10] FIG. 10 is a plan view schematically showing a first substrate and a second substrate of a Peltier module according to Modification 2. [Figure 11] FIG. 11 is a plan view schematically showing a first substrate and a second substrate of a Peltier module according to Modification 3. [Figure 12] FIG. 12 is a plan view schematically showing a first substrate and a second substrate of a Peltier module according to Modification 4. [Figure 13] FIG. 13 is a plan view schematically showing a first substrate and a second substrate of a Peltier module according to Modification 5. [Figure 14] FIG. 14 is a plan view schematically showing a first substrate and a second substrate of a Peltier module according to Modification 6. [Figure 15] FIG. 15 is a cross-sectional view schematically showing a first substrate and a second substrate of a Peltier module according to Modification 6.

MODE FOR CARRYING OUT THE INVENTION

[0010] Hereinafter, embodiments according to the present disclosure will be described with reference to the drawings, but the present disclosure is not limited to the embodiments. The components of the plurality of embodiments described below can be combined as appropriate. Also, some components may not be used.

[0011] In the embodiments, the terms “left”, “right”, “front”, “rear”, “upper”, and “lower” are used to describe the positional relationships of the respective parts. These terms indicate the relative position or direction based on the center of the optical communication device 1. The left-right direction, the front-rear direction, and the up-down direction are orthogonal to each other.

[0012] (First Embodiment) [Optical Communication Device] FIG. 1 is a plan view schematically showing an optical communication device according to the first embodiment. FIG. 2 is a cross-sectional view schematically showing the optical communication device according to the first embodiment.

[0013] As shown in FIGS. 1 and 2, the optical communication device 1 includes a case 2 and a Peltier module 10 disposed in the internal space of the case 2.

[0014] The case 2 is made of metal. The case 2 has a lid portion 2A, a bottom portion 2B disposed opposite to the lid portion 2A, and a side wall portion 2C disposed between the lid portion 2A and the bottom portion 2B. The lid portion 2A is disposed so as to cover the upper opening of the case 2. The internal space of the case 2 is designed according to the outer shape of the Peltier module 10. In the embodiment, the internal space of the case 2 is designed according to the outer shape of the substrate having a larger area among the first substrate 11 and the second substrate 12 of the Peltier module 10. The internal space of the case 2 is sealed. The internal space of the case 2 is filled with dry air or an inert gas. The inert gas is, for example, argon gas, nitrogen gas, and helium gas. The internal space of the case 2 may be a vacuum. The lower surface of the lower portion of the case 2 is a heat dissipation surface.

[0015] [Peltier Module] As shown in FIG. 2, the Peltier module 10 includes a first substrate 11 and a second substrate 12 which are a pair of substrates, and a thermoelectric conversion element 21 disposed between the first substrate 11 and the second substrate 12. The arrangements of the thermoelectric conversion element 21, the first electrode 22, and the second electrode 23 in each figure used in the following description are schematically shown.

[0016] The Peltier module 10 has different areas of the first substrate 11 and the second substrate 12. In the Peltier module 10, the first substrate 11 is smaller than the second substrate 12 in the width direction or the entire circumference. Alternatively, in the Peltier module 10, the second substrate 12 is smaller than the first substrate 11 in the width direction or the entire circumference. In the embodiment, the Peltier module 10 in which the first substrate 11 is smaller than the second substrate 12 in the entire circumference will be described.

[0017] Figure 3 is a schematic plan view of the first substrate of the Peltier module according to the first embodiment, viewed from above. Figure 4 is a schematic plan view of the second substrate of the Peltier module according to the first embodiment, viewed from below. The first substrate 11 and the second substrate 12 are formed of an electrically insulating material. As shown in Figures 3 and 4, the first substrate 11 and the second substrate 12 are arranged opposite each other with the thermoelectric conversion element 21 in between. In this embodiment, the second substrate 12 is positioned above the first substrate 11. The first substrate 11 and the second substrate 12 are formed in a plate shape. In this embodiment, the first substrate 11 and the second substrate 12 are formed in a rectangular shape.

[0018] Figure 5 is a schematic plan view showing the first and second substrates of a Peltier module according to the first embodiment. In this embodiment, the first substrate 11 is one of a pair of substrates, and the second substrate 12 is the other substrate. The first substrate 11 has a difference in length from the second substrate 12 in at least one direction.

[0019] "At least one direction" means including one of the directions that define the outer shapes of the first substrate 11 and the second substrate 12.

[0020] In this embodiment, the first substrate 11 has shorter sides than the second substrate 12. The second substrate 12 has shorter sides in the left-right direction and in the front-back direction than the first substrate 11. The area of ​​the second substrate 12 in the vertical direction is larger than the area of ​​the first substrate 11. In this embodiment, in the vertical direction, the first substrate 11 is smaller than the second substrate 12 around its entire circumference. In this embodiment, in the vertical direction, the outer edge of the first substrate 11 is located inward from the outer edge of the second substrate 12. The difference between the left edges of the second substrate 12 and the first substrate 11 is d1. The difference between the right edges of the second substrate 12 and the first substrate 11 is d2. The difference between the rear edges of the second substrate 12 and the first substrate 11 is d3. The difference between the front edges of the second substrate 12 and the first substrate 11 is d4. The difference in the left-right side lengths of the second substrate 12 and the first substrate 11 is d1 + d2. The difference in the lengths of the front-to-back sides of the second substrate 12 and the first substrate 11 is d3 + d4.

[0021] A larger difference in the side lengths of the first substrate 11 and the second substrate 12 is desirable because it allows for greater absorption of positional displacement. The difference in side lengths of the first substrate 11 and the second substrate 12 is more preferably greater than 50 μm and more preferably greater than 100 μm. There is no upper limit specified for the difference in side lengths of the first substrate 11 and the second substrate 12.

[0022] The difference in the side lengths of the first substrate 11 and the second substrate 12 is less than twice the distance between adjacent first electrodes 22 and the distance between adjacent second electrodes 23.

[0023] When the difference in the side lengths of the first substrate 11 and the second substrate 12 is large, the area on which the thermoelectric conversion element 21 can be mounted (referred to as the "element mounting area") becomes smaller. The element mounting area is the cross-sectional area of ​​the space sandwiched between the first substrate 11 and the second substrate 12. The maximum heat absorption of the Peltier module 10 is proportional to the total cross-sectional area of ​​the thermoelectric conversion element 21 within the Peltier module 10, and therefore is approximately proportional to the element mounting area. Consequently, if the difference in side lengths is large, the maximum heat absorption of the Peltier module 10 may decrease. For this reason, it is desirable that the area of ​​the element mounting area be 0.8 times or more, more preferably 0.9 times or more, and more preferably 0.95 times or more, the area of ​​the substrate with the larger side length. As a result, according to this embodiment, it is possible to provide a Peltier module 10 with high external shape accuracy while suppressing a decrease in the maximum heat absorption of the Peltier module 10.

[0024] As shown in Figure 2, one or more thermoelectric elements 21 are arranged between the upper surface 11a of the first substrate 11 and the lower surface 12a of the second substrate 12. Multiple thermoelectric elements 21 are connected by multiple first electrodes 22 and second electrodes 23.

[0025] The thermoelectric element 21 is formed from a thermoelectric material. Examples of thermoelectric materials for forming the thermoelectric element 21 include manganese silicide compounds (Mn-Si), magnesium silicide compounds (Mg-Si-Sn), skutterudite compounds (Co-Sb), half-heusla compounds (Zr-Ni-Sn), and bismuth telluride compounds (Bi-Te). The thermoelectric element 21 may be composed of one compound selected from manganese silicide compounds, magnesium silicide compounds, skutterudite compounds, half-heusla compounds, or bismuth telluride compounds, or it may be composed of a combination of at least two compounds.

[0026] The thermoelectric conversion element 21 includes a p-type element 21P and an n-type element 21N. Multiple p-type elements 21P and n-type elements 21N are arranged within a predetermined plane. In the front-to-back direction, the p-type elements 21P and n-type elements 21N are arranged alternately. In the left-to-right direction, the p-type elements 21P and n-type elements 21N are arranged alternately.

[0027] The first electrode 22 and the second electrode 23 are made of a conductive metal. The first electrode 22 is positioned between the first substrate 11 and the thermoelectric conversion element 21. The first electrode 22 and the second electrode 23 connect the thermoelectric conversion element 21. The first electrode 22 is provided on the upper surface 11a of the first substrate 11. Multiple first electrodes 22 are provided in a predetermined plane parallel to the upper surface 11a of the first substrate 11. The second electrode 23 is positioned between the second substrate 12 and the thermoelectric conversion element 21. The second electrode 23 is provided on the lower surface 12a of the second substrate 12. Multiple second electrodes 23 are provided in a predetermined plane parallel to the lower surface 12a of the second substrate 12.

[0028] The first electrode 22 and the second electrode 23 are connected to adjacent pairs of p-type elements 21P and n-type elements 21N, respectively. The first electrode 22 and the second electrode 23 connect multiple thermoelectric elements 21 in series. The first electrode 22 and the second electrode 23 form a series circuit in which multiple thermoelectric elements 21 are connected in series. By electrically connecting the p-type elements 21P and n-type elements 21N via the first electrode 22 and the second electrode 23, a pair of pn elements is formed. By connecting multiple pairs of pn elements in series via the first electrode 22 and the second electrode 23, a series circuit including multiple thermoelectric elements 21 is formed.

[0029] When current is supplied to the thermoelectric conversion element 21, the Peltier module 10 absorbs or generates heat due to the Peltier effect. This effect is used to regulate the temperature of the optical component 100 placed on top of the Peltier module 10.

[0030] The lower surface of the first substrate 11 is the heat dissipation surface of the Peltier module 10. The upper surface 12b of the second substrate 12 is the temperature control surface of the Peltier module 10.

[0031] [Optical communication equipment] The optical communication device is constructed using a Peltier module 10. The optical communication device mounts optical components 100 directly onto the upper surface 12b of the second substrate 12 of the Peltier module 10. As shown in Figures 1 and 2, the optical components 100 (although the optical components are omitted in the drawings) are arranged on the upper surface 12b of the second substrate 12. The electrode pattern 101 is a wiring pattern for the optical components. The through-hole 102 is a through-hole.

[0032] In the Peltier module 10 configured in this way, the first substrate 11 is smaller than the second substrate 12 around its entire circumference. When viewed in the vertical direction, the outer edge of the first substrate 11 is located inward from the outer edge of the second substrate 12.

[0033] [Assembly method and operation] Figure 6 is a schematic cross-sectional view showing the first and second substrates of a Peltier module according to the first embodiment. Here, we will describe the assembly method of the first substrate 11 and the second substrate 12 of the Peltier module 10. The first substrate 11 is provided with a first electrode 22 and a second electrode 23. The first electrode 22 is provided on the upper surface 11a of the first substrate 11. A thermoelectric conversion element 21 is connected to the upper surface of the first electrode 22. The second electrode 23 is provided on the lower surface 12a of the second substrate 12. As shown in Figure 6, the first substrate 11 and the second substrate 12 are bonded together after being aligned so that the first substrate 11 is positioned inward relative to the second substrate 12 in a vertical view.

[0034] More specifically, with the upper surface 11a of the first substrate 11 facing upwards and the lower surface 12a of the second substrate 12 facing downwards, the second substrate 12 is brought closer to the first substrate 11 from above. The positions of the first substrate 11 and the second substrate 12 are aligned so that, in a vertical view, the outer edge of the first substrate 11 does not extend beyond the outer edge of the second substrate 12. During alignment, a predetermined range of deviation is permitted in the left-right and depth directions. Then, the second electrode 23 provided on the second substrate 12 is connected to the thermoelectric conversion element 21 provided on the first substrate 11 via the first electrode 22.

[0035] Figure 7 is a schematic plan view showing the first and second substrates of the Peltier module according to the first embodiment. Figure 8 is a schematic cross-sectional view showing the first and second substrates of the Peltier module according to the first embodiment. In the example shown in Figures 7 and 8, the second substrate 12 is shifted to the right relative to the first substrate 11. The positional shift of the second substrate 12 relative to the first substrate 11 is indicated by L.

[0036] As shown in Figures 7 and 8, even if the second substrate 12 is misaligned relative to the first substrate 11, the misalignment is absorbed by the difference in the side lengths of the first substrate 11 and the second substrate 12. This makes it less likely for the first substrate 11 to protrude from the second substrate 12 when viewed in the vertical direction. Furthermore, a Peltier module 10 with improved external shape accuracy is provided.

[0037] Even if the second substrate 12 is misaligned relative to the first substrate 11, the thermoelectric conversion element 21 will be connected to the appropriate second electrode 23 to which it should be connected, and will not come into contact with any unintended second electrode 23.

[0038] [effect] In this embodiment, the length of each side of the first substrate 11 is smaller than the length of each side of the second substrate 12 around its entire circumference. In this embodiment, the first substrate 11 is aligned so that it is positioned inward relative to the second substrate 12 when viewed in the vertical direction, and the first substrate 11 and the second substrate 12 are bonded together. According to this embodiment, the difference in the lengths of the first substrate 11 and the second substrate 12 can absorb any positional misalignment between them. In this way, the embodiment can provide a Peltier module 10 with improved external shape accuracy.

[0039] Furthermore, according to the embodiment, the space required to mount the Peltier module 10 can be reduced by the amount of improvement in external shape accuracy, allowing for the design of the optical communication device. According to the embodiment, the optical communication device equipped with the Peltier module 10 can be made even smaller. In this way, the embodiment can provide a Peltier module 10 with improved external shape accuracy that can be installed in a limited space, and an optical communication device that can be installed in a limited space.

[0040] Next, we will explain the case where the lengths of each side of the first substrate 11 and the second substrate 12 are the same. When assembling the Peltier module 10, the first substrate 11 and the second substrate 12 are aligned so that all their end faces meet, and one substrate is brought close to the other substrate and bonded together. As a result, the first substrate 11 and the second substrate 12 are bonded together with a misalignment, depending on the precision of the bonding equipment or the skill of the worker. In this case, the outer shape of the Peltier module 10 becomes larger by the amount of the misalignment.

[0041] As shown in the embodiment, an optical communication device is described that uses a Peltier module 10 having an electrode pattern on the upper surface 12b of a second substrate 12, and in a later process, optical components 100 are directly mounted on the upper surface 12b of the second substrate 12. According to the embodiment, by making the first substrate 11 smaller, the position of the electrode pattern 101 can be made unaffected by the misalignment of the first substrate 11 and the second substrate 12.

[0042] In the embodiment, a larger difference in the side lengths of the first substrate 11 and the second substrate 12 is desirable because it allows for greater absorption of misalignment. In the embodiment, the difference in side lengths is more preferably greater than 50 μm, and even more preferably greater than 100 μm. In addition, in the embodiment, increasing the difference in side lengths may reduce the maximum heat absorption capacity of the Peltier module 10. Therefore, in the embodiment, it is desirable that the area of ​​the element mounting portion be 0.8 times or more, more preferably 0.9 times or more, and more preferably 0.95 times or more, the area of ​​the substrate with the larger side length. As a result, according to the embodiment, it is possible to provide a Peltier module 10 with high external shape accuracy while suppressing a decrease in the maximum heat absorption capacity of the Peltier module 10.

[0043] In this embodiment, the difference in the side lengths of the first substrate 11 and the second substrate 12 is smaller than the distance between adjacent first electrodes 22 and the distance between adjacent second electrodes 23. According to this embodiment, even if the positions of the first substrate 11 and the second substrate 12 are misaligned, the thermoelectric conversion element 21 can be positioned to connect to the appropriate second electrode 23.

[0044] In particular, for an optical communication device that uses a Peltier module 10 having an electrode pattern 101 on the upper surface 12b of the upper substrate, the second substrate 12, and mounts optical components 100 directly onto the second substrate 12 in a later process, reducing the size of the lower substrate, the first substrate 11, eliminates the influence of misalignment in the substrate bonding on the position of the electrode pattern 101 relative to the outer shape of the Peltier module 10. As a result, the electrode pattern 101 is positioned more accurately, which is useful for precisely positioning the optical components 100.

[0045] (Variation 1) Figure 9 is a schematic plan view showing the first and second substrates of a Peltier module according to Modification 1. In the Peltier module 10 shown in Figure 9, the first substrate 11 is smaller than the second substrate 12 in the front-to-back direction. The length of the sides of the second substrate 12 in the left-to-right direction is the same as that of the first substrate 11. The length of the sides of the second substrate 12 in the front-to-back direction is shorter than that of the first substrate 11. The width of the first substrate 11 and the second substrate 12 is the same in the left-to-right direction. The depth of the first substrate 11 and the second substrate 12 is different in the front-to-back direction. In Modification 1, the depth of the first substrate 11 is shorter than the depth of the second substrate 12. In Modification 1, when aligning the positions of the first substrate 11 and the second substrate 12, the positions are aligned so that the positions of the ends do not shift in the left-to-right direction. When aligning the positions of the first substrate 11 and the second substrate 12, a positional shift in the depth direction is permitted as long as the first substrate 11 is not exposed from the second substrate 12.

[0046] (Modification 2) Figure 10 is a schematic plan view showing the first and second substrates of a Peltier module according to Modification 2. In the Peltier module 10 shown in Figure 10, the first substrate 11 is smaller than the second substrate 12 around its entire circumference. In a vertical view, the outer edge of the first substrate 11 is located inward from the outer edge of the second substrate 12. The first substrate 11 and the second substrate 12 have notches 111 and 112. The first substrate 11 has a notch 111 on its right rear side. The second substrate 12 has a notch 112 on its right rear side. When aligning the first substrate 11 and the second substrate 12, positional misalignment is permitted in the left-right and depth directions, as long as the first substrate 11 is not exposed from the second substrate 12.

[0047] (Variation 3) Figure 11 is a schematic plan view showing the first and second substrates of a Peltier module according to Modification 3. In the Peltier module 10 shown in Figure 11, the first substrate 11 is smaller than the second substrate 12 in the front-to-back direction. The first substrate 11 and the second substrate 12 have different widths in the left-to-right direction and depths in the front-to-back direction. In Modification 11, the left-to-right width of the first substrate 11 is longer than the left-to-right width of the second substrate 12. In Modification 11, the depth of the first substrate 11 is shorter than the depth of the second substrate 12. In the example shown in Figure 11, the first substrate 11 protrudes to the right of the second substrate 12 on the right side. End electrodes 31 and 32 are arranged on the protruding portion on the upper surface 11a of the first substrate 11 that extends to the right of the second substrate 12.

[0048] The protruding portion extends outward by 300 μm or more in the rightward direction. The protruding portion may be located in other positions as long as it extends outward by 300 μm or more in at least one direction.

[0049] The end electrodes 31 and 32 are electrode leads for power supply. The end electrodes 31 and 32 are electrodes for extracting power from the circuit to the outside. The end electrodes 31 and 32 are made of a conductive metal. The end electrodes 31 and 32 are provided on the protruding portion of the upper surface 11a of the first substrate 11. The end electrode 31 is connected to the thermoelectric conversion element 21 at one end of the circuit. The end electrode 32 is connected to the thermoelectric conversion element 21 at the other end of the circuit.

[0050] (Modification 4) Figure 12 is a schematic plan view showing the first and second substrates of a Peltier module according to modified example 4. In the Peltier module 10 shown in Figure 12, the first substrate 11 is smaller than the second substrate 12 in the left-right and front-back directions. The first substrate 11 is rectangular. The second substrate 12 has a notch 121. The second substrate 12 has a notch 121 on its right rear side. The first substrate 11 and the second substrate 12 have different widths in the left-right direction and depths in the front-back direction. The left-right width of the first substrate 11 is shorter than the left-right width of the second substrate 12. The depth of the first substrate 11 is shorter than the depth of the second substrate 12. In the example shown in Figure 12, the right rear portion of the first substrate 11 is exposed through the notch 121 of the second substrate 12. End electrodes 31 and 32 are arranged on the exposed portion of the first substrate 11.

[0051] (Variation 5) Figure 13 is a schematic plan view showing the first and second substrates of a Peltier module according to modified example 5. In the Peltier module 10 shown in Figure 13, the second substrate 12 is smaller than the first substrate 11 in the left-right and front-back directions. The first substrate 11 is rectangular in shape. The second substrate 12 has a notch 112. The second substrate 12 has a notch 112 on its right rear side. The first substrate 11 and the second substrate 12 have different widths in the left-right direction and different depths in the front-back direction. The left-right width of the first substrate 11 is longer than the left-right width of the second substrate 12. The depth of the first substrate 11 is longer than the depth of the second substrate 12. In the example shown in Figure 13, the right rear portion of the first substrate 11 is exposed through the notch 121 of the second substrate 12. End electrodes 31 and 32 are arranged on the exposed portion of the first substrate 11.

[0052] The second substrate 12 is aligned so that it is positioned inward relative to the first substrate 11 when viewed from above, and the first substrate 11 and the second substrate 12 are bonded together. The positional misalignment is absorbed by the amount that the second substrate 12 is smaller than the first substrate 11.

[0053] (Experimental variation 6) Figure 14 is a schematic plan view showing the first and second substrates of the Peltier module according to Modification 6. Figure 15 is a schematic cross-sectional view showing the first and second substrates of the Peltier module according to Modification 6. In the Peltier module 10 shown in Figure 14, the second substrate 12 is smaller than the first substrate 11 in the left-right and front-back directions. The first substrate 11 and the second substrate 12 are configured in the same way as in Modification 5. The end electrodes 31 and 32 have a post structure. The end electrode 31 has a columnar portion 31H erected upward from the upper surface 11a of the first substrate 11. The end electrode 32 has a columnar portion 32H erected upward from the upper surface 11a of the first substrate 11. [Explanation of Symbols]

[0054] 1...Optical communication device, 2...Case, 2A...Lid, 2B...Bottom, 2C...Side wall, 10...Peltier module, 11...First substrate, 11a...Top surface, 12...Second substrate, 12a...Bottom surface, 12b...Top surface, 21...Thermoelectric conversion element, 21P...p-type element, 21N...n-type element, 22...First electrode, 23...Second electrode, 31...End electrode (electrode lead-out section), 32...End electrode (electrode lead-out section), 100...Optical component, 101...Electrode pattern, 102...Through hole.

Claims

1. A Peltier module used in optical communications, A pair of circuit boards arranged facing each other, A plurality of thermoelectric elements disposed between the pair of substrates, The electrodes to which the thermoelectric element is connected, Equipped with, The upper of the pair of substrates has a difference in length in at least one direction relative to the lower substrate. The difference is such that the length in one direction is longer for the upper substrate of the pair than for the lower substrate. The aforementioned difference is narrower than the distance between adjacent electrodes. Peltier module.

2. The aforementioned difference is greater than 0 μm. The Peltier module according to claim 1.

3. The aforementioned difference is greater than 50 μm. The Peltier module according to claim 2.

4. The aforementioned difference is greater than 100 μm. The Peltier module according to claim 2.

5. The area of ​​the lower substrate of the pair of substrates is 0.8 times or more the area of ​​the upper substrate. The Peltier module according to claim 1.

6. The area of ​​the lower substrate of the pair of substrates is 0.9 times or more the area of ​​the upper substrate. The Peltier module according to claim 5.

7. The area of ​​the lower substrate of the pair of substrates is 0.95 times or more the area of ​​the upper substrate. The Peltier module according to claim 5.

8. The lower of the pair of substrates has an overhang that extends outward by at least 300 μm in one direction relative to the upper substrate. Equipped with, An end electrode, which is an electrode lead-out portion for power supply, is arranged in the aforementioned protruding portion. A Peltier module according to any one of claims 1 to 7.

9. The upper of the pair of substrates has a notch, Equipped with, An end electrode, which is an electrode lead-out portion for power supply, is positioned in the aforementioned cutout portion. A Peltier module according to any one of claims 1 to 7.

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