JP2002237645A - Light-emitting element carrier, light-emitting element module, light-emitting element and light-emitting element driving method - Google Patents

Abstract

PROBLEM TO BE SOLVED: To obtain a light-emitting element, having temperature compensation function of optical output, a light-emitting element module, and a light-emitting element carrier inside the module. SOLUTION: The light-emitting element carrier is applied to a light-emitting element driving method, wherein a parallel circuit of a thermistor 102 whose resistance has negative temperature characteristic and a resistor element 103 is connected, in series with the light-emitting element of current driving type. The thermistor 102 and the resistor element 103 are formed into a film type on the surface of a base part 101 of the light-emitting element carrier, on which surface a light emitting element is to be mounted.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a light-emitting element module and a light-emitting element used in an optical transmitter of an optical transmission system, a light-emitting element carrier therein, and a driving method thereof.

[0002]

2. Description of the Related Art An optical transmission system is characterized by being superior in characteristics such as transmission speed, transmission distance, and electromagnetic induction noise as compared with an electric transmission system. Particularly in a short distance, a parallel optical transmission system for transmitting many signals in parallel has been developed.

[0003] In order to reduce the cost of such an optical transmission system, it is necessary to simplify the circuits for transmission and reception as well as the technology for coupling the light emitting element and the light receiving element with the optical fiber (optical mounting). And LD (Laser Di) is used as a light emitting element.
ode). Circuits used in the optical transmitter include an LD drive circuit and a temperature control circuit. L
The D drive circuit usually includes two current sources, a bias current and a modulation current, and controls the bias current for APC (Auto Power Control). LD as the temperature control circuit
There is a type that controls a Peltier element by using a thermistor attached near a carrier as a temperature sensor. As a result, the wavelength and light output of the LD are stably maintained against environmental temperature changes and changes over time in the device characteristics of the LD.

However, in an optical transmitter for short distance,
These temperature sensors and Peltier elements may be simplified or omitted in order to allow a reduction in the accuracy of the stability of the LD and to reduce the cost.

[0005] An example of an LD drive system with a simple temperature compensation function for stably maintaining the light output irrespective of a temperature change will be described. Also called). One example in JP-A-11-121852 (Fujitsu) shown in FIG.
This relates to temperature compensation of optical output when the LD 201 is directly driven by the output stage transistor 203 of the logic circuit 202. Here, a parallel circuit of a thermistor 204 (a resistance element having a negative temperature characteristic is also referred to as a thermistor in this specification) and a resistance 205 is connected in series between the output stage transistor 203 and the LD 201.

In general, the threshold current of the LD 201 increases as the temperature rises, and the optical output decreases during constant current driving. On the other hand, the resistance of the thermistor 204 decreases as the temperature rises. Therefore, since the output of the logic circuit 202 is a constant voltage output, when the resistance value of the thermistor 204 decreases, the combined resistance of the parallel circuit of the thermistor 204 and the resistor 205 decreases, the output current increases, and the As a result, the reduction in the optical output of the LD 201 is compensated to some extent. This is one of the simple methods of the feedforward APC in which the drive current of the LD 201 increases with the temperature rise.

[0007] The invention of the above publication relates to a circuit configuration and does not specifically describe the mounting of a thermistor. In a normal LD module, a thermistor is directly mounted on a mount substrate, while an LD chip is mounted on a mount substrate via an LD carrier. In this mounting mode, an error occurs in the temperature compensation control due to the thermal resistance of the material between the thermistor and the LD chip.

As a method of reducing this control error, Japanese Patent Application Laid-Open No. 08-335747 (Anritsu) discloses a method of forming a thermistor thin film on an LD carrier on which an LD chip is mounted (referred to as a heat sink in the specification of this publication). , The thermal resistance is reduced. FIG. 9 shows the configuration. The LD carrier 901 (heat sink) is a non-conductive heat conductor having good heat conductivity, and a thermistor thin film 903 is formed near the mounting location of the LD chip 902. The electrodes of the thermistor thin film 903 (omitted in FIG. 9) are electrically insulated from the electrodes of the LD chip 902 (omitted in FIG. 9). Thermistor 903 is connected to the sensor input of the temperature control circuit and
The temperature of a mount substrate below the D carrier 901 (referred to as a carrier in the specification of this publication) is controlled.
An example of the resistance value of the thermistor 903 is 10 kΩ.

[0009]

SUMMARY OF THE INVENTION
When the normal thermistor mounting (where a thermistor component is mounted on a mount) is applied to the LD driving method disclosed in Japanese Patent Application Laid-Open No. 11-121852, there are the following problems. First, the current path of the LD becomes longer due to the mounting distance between the thermistor and the LD, making it difficult to improve the frequency characteristics of the module. Second, it is difficult to further reduce the thermal resistance between the thermistor and the LD. Third, if the cost is further reduced, the component cost and the mounting cost of the thermistor become problems.

On the other hand, the LD carrier with a thermistor thin film disclosed in Japanese Patent Application Laid-Open No. 08-335747 can solve the above-mentioned problems to some extent, but cannot be applied to the LD driving method disclosed in Japanese Patent Application Laid-Open No. 11-121852.

An object of the present invention is to provide a light emitting element such as an LD or LED having a temperature compensation function of an optical output suitable for the LD driving method disclosed in Japanese Patent Application Laid-Open No. 11-121852, a light emitting element module, a light emitting element carrier therein, And a method of driving the light emitting element, whereby the characteristics of the light emitting element can be improved and the cost can be reduced.

[0012]

According to the present invention, there is provided a light-emitting element carrier according to the present invention, wherein a parallel circuit of a resistance element having a negative temperature characteristic (referred to as a thermistor in this specification) and a resistance element is driven by current. The present invention is particularly effective in an LD such as an edge emitting laser or a surface emitting laser, but is an LE.
A light-emitting element carrier applied to a light-emitting element driving system connected in series with a light-emitting element carrier, wherein a surface (light-emitting element) of a base of the light-emitting element carrier (light-emitting element carrier base) is mounted. The invention is characterized in that the thermistor and the resistance element are formed in a film shape on a mounting surface.

In the light emitting device carrier of the present invention, a thermistor and a resistor film are formed on the light emitting device mounting surface of the light emitting device carrier base. By mounting the light emitting element on the electrode film formed in contact with all or a part of the thermistor film and the resistance film, a parallel circuit of the thermistor and the resistor and the light emitting element mounted in series become one component. By driving this light at a constant voltage, the light output of the light emitting element is temperature compensated. In this configuration, the temperature compensation parameter is increased by combining the thermistor and the resistor compared to the thermistor alone,
The accuracy of the temperature compensation function can be improved.

Further, since the light emitting element is mounted on the thermistor film, the thermal resistance of the material between the light emitting element and the thermistor can be reduced. Therefore, external environment or light emitting element,
The performance of the temperature compensating mechanism can be enhanced by lowering the resistance of the thermistor (ie, increasing the driving current of the light emitting element) in response to a temperature increase due to the heat generated by the thermistor and the resistor. Further, since the wiring between the light emitting element and the thermistor is not interposed, the current path can be shortened, and deterioration of frequency characteristics due to parasitic inductance can be avoided. Also,
Since the thermistor and the resistor are integrated with the light emitting element carrier, component costs and mounting costs can be reduced.

In the above basic configuration, the following forms can be adopted. The light emitting element mounting surface may include a conductive portion, and the thermistor and the resistor may be formed in a film on the conductive portion. Thereby, the light emitting element can be stacked and mounted on the light emitting element carrier via the thermistor film, the resistance film and the electrode film, and the thermal resistance and the parasitic capacitance can be reduced. In addition, a film can be formed by a simple method such as a thick film technique, and cost can be reduced.

Here, each of the thermistor and the resistance element may be one rectangular or rectangular film. Thereby, the shape of the film is simplified, and the cost can be reduced.

The thermistor and the resistance element may be a plurality of strip-shaped films, and may be formed alternately. Thereby, the distribution of the thermistor and the resistance on the light emitting element mounting surface of the light emitting element carrier can be averaged, and the tolerance of the mounting position of the light emitting element can be increased.

One of the thermistor and the resistance element may be a lattice-like film, and the other may be a plurality of films disposed in openings of the lattice-like film. This allows
The distribution of the thermistor and the resistance on the light emitting element mounting surface of the light emitting element carrier can be further averaged, and the tolerance of the light emitting element mounting position can be further increased.

The light emitting element mounting surface has a conductive region and an insulating region, and the thermistor and the film of the resistance element are formed over two regions of the conductive region and the insulating region. You can do it. As a result, a current flows in the thermistor and the resistor in a direction parallel to the film, so that the range of setting the resistance value according to the shape of the film can be expanded, and the range of material selection can be expanded. In addition, thin film technology can be applied, and manufacturing accuracy of a film shape can be improved.

Here, each of the thermistor and the resistance element may be a comb-shaped film, one rectangular or rectangular film, or a plurality of strip films. Here, it becomes easy to design the resistance value according to the shape of the film.

The light emitting element carrier base is made of a conductive material, and an insulating film is formed on a part of the light emitting element mounting surface. Accordingly, a metal material having high thermal conductivity and a low price can be used as the material of the light emitting element carrier base, and the heat radiation characteristics can be improved and the cost can be reduced.

Further, the light emitting element carrier base may be made of an insulating material, and a conductive film may be formed on a part of the light emitting element mounting surface. Thereby, the capacity of the light emitting element carrier can be reduced, and the deterioration of the frequency characteristics when the light emitting element module is configured can be prevented.

Further, a light emitting element module that achieves the above object is characterized in that a light emitting element is mounted on the light emitting element mounting surface of the light emitting element carrier. As a result, the temperature characteristics are compensated to some extent at low cost (temperature compensation).
The light emitting element module can be realized. In this case, typically, the light emitting element is mounted on an electrode film formed in contact with all or a part of the thermistor film and the resistance film. In this way, a component in which a parallel circuit of a thermistor and a resistor and a light emitting element are mounted in series is one component. By driving this light at a constant voltage, the light output of the light emitting element is temperature compensated.

Further, a light emitting element for achieving the above object is a light emitting element applied to a light emitting element driving system in which a parallel circuit of a thermistor having a negative temperature characteristic and a resistance element is connected in series to a current driven light emitting element. An element, wherein the thermistor and the resistance element are formed in a film shape on an electrode of the light emitting element.

This is because a portion indicated by reference numeral 101 in FIGS. 1, 5, and 7 is considered to be a light emitting element having an electrode on an upper surface, and a thermistor and a resistance element are formed on the light emitting element. Have. Film formation or fixation of the thermistor and the resistive element on the light emitting element electrode (film formation of the thermistor and the resistive element on a substrate (this substrate can be left as it is if the substrate is an electrode) and fixation on the light emitting element electrode) It must be performed at a temperature that does not damage the light emitting element.

Further, a light-emitting element driving method for achieving the above object is characterized in that the light-emitting element carrier, the light-emitting element module, or the light-emitting element is used at a constant voltage. As a result, the performance of compensating for the temperature characteristics of the light emitting element can be improved and the cost can be reduced.

[0027]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS The embodiments of the present invention will be described below with reference to the accompanying drawings. Since an LD is mainly used as a light emitting element, an LD such as an edge emitting laser or a surface emitting laser will be described as a light emitting element in the following embodiments. Accordingly, the light emitting element carrier is used as an LD carrier. The following embodiments are not limited to LDs, and can be applied to LEDs (Light Emitting Diodes).

(First Embodiment) Hereinafter, a first embodiment of the present invention will be described in detail with reference to the drawings. FIG. 1 is a configuration diagram of a first embodiment of the LD carrier of the present invention. The upper part is a top view and the lower part is a front view (the surface on which the end surface from which the light of the LD (edge emitting laser) is emitted is mounted). In FIG. 1, 101
Denotes an LD carrier base (the whole shown in FIG. 1 is an LD carrier, which means the base); 102, a thermistor film (shown by horizontal stripes in FIG. 1); 103, a resistive film (FIG. 1)
Reference numeral 104 denotes an electrode film. In addition, since the top view shows the shapes of the thermistor film 102 and the resistance film 103, the electrode film 104 is omitted. The anode or cathode side of the LD is mounted on the electrode film 104. Thermistor film 102 and resistive film 103
Are extremely small in comparison with their plane size, so that they may or may not be in contact. That is, if the LD is mounted at the center in the form shown in FIG. 1, a parallel circuit of the thermistor film 102 and the resistance film 103 will be connected to the LD. LD carrier base 101
Is conductive, which is grounded or connected to the logic circuit side.

FIG. 2 is a diagram showing an L to which the LD carrier of the present invention is applied.
FIG. 4 is a circuit diagram of the first example of the D driving method described above. In FIG. 2, 2
01 is LD, 202 is logic circuit, 203 is logic circuit 202
, An output transistor 204, a thermistor 204, and a resistor 205. Vcc indicates a positive power supply (for example, 5 V or 3.3 V), GND indicates ground, and DATA indicates a data signal input to the logic circuit 202.

By connecting the resistor 205 to the thermistor 204 in parallel, the number of parameters for setting the relationship between the element temperature of the LD 201 and the drive current increases, and the accuracy of temperature characteristic compensation (temperature compensation accuracy) of the LD 201 can be increased. In this example, a parallel circuit of the thermistor 204 and the resistor 205 is connected to the anode of the LD 201. Therefore, the electrode film 104 of the LD carrier
Is mounted on the anode side of the LD 201. Then, the LD carrier becomes floating (neither terminal is grounded).

FIG. 3 is a graph showing an L value to which the LD carrier of the present invention is applied.
It is a circuit diagram of the 2nd example of a D drive system. The components are the same as in FIG. The difference is the connection order of the parallel circuit of the thermistor 204 and the resistor 205 and the connection of the LD 201 between the output transistor 203 of the logic circuit 202 and GND. In this example, a parallel circuit of the thermistor 204 and the resistor 205 is connected to the cathode of the LD 201. Therefore, the cathode side of the LD 201 is mounted on the electrode film 104 of the LD carrier. This form is LD2
01 floats, but the LD carrier base 10
The bottom surface of 1 is grounded, and the mounting mode of the LD carrier is normal (not the normal mode of mounting the LD 201).

FIG. 4 is a graph showing L to which the LD carrier of the present invention is applied.
It is a block diagram of a D module. FIG. In FIG. 4, reference numeral 401 denotes an LD carrier, and 402 denotes an LD chip (here, an edge emitting laser chip. However, a surface emitting laser chip may be used. In this case, light is emitted from the side opposite to the side where the LD carrier is located. 403 is a logic circuit IC chip, 404 is an LD chip 402 and a logic circuit
Bonding wire connecting IC chip 403, 405 is LD
Bonding wire for connecting the carrier 401 and the logic circuit IC chip 403; 406, an LD module package; 4
07 is a circuit board, 408 is an optical mount, 409 is an electrical connection terminal, and 410 is an optical fiber.

In this configuration, the LD chip 402 is mounted on the upper surface of the LD carrier 401 as described above, and the LD carrier 401 and the optical fiber 410 are mounted on the optical mount 408. On the optical mount 408, a wiring pattern for mounting the LD carrier 401 is formed. Logic circuit IC chip 403
Are mounted on the circuit board 407. On the circuit board 407, a wiring pattern for mounting the logic circuit IC chip 403 is formed. The connection between the LD carrier 401 and the logic circuit IC chip 403 is made via these wiring patterns.

In this embodiment, a rectangular or rectangular thermistor film 102 and a resistance film 103 are formed on the upper surface of the electrically conductive LD carrier base 101 as described above, and an electrode film 104 is formed on the upper surface of these films. Then, the LD chip 201 is mounted on the upper surface.

As the LD carrier base 101, a metal material of copper or an alloy of copper and tungsten (in some cases, gold plating may be applied to the entire surface), or a ceramic material (SiC , AlN, etc.). The thermistor film 102 and the resistive film 103 are formed by using a thick film technique (sintering after screen printing) (thick films are roughly 1 to
It has a thickness of 10 μm or more, and a thickness of about 1 to 10 μm or less is a thin film). The material of the thermistor film 102 is NTC (Negative Temperatur), whose resistance decreases with increasing temperature.
e Coefficient). As a thermistor material, there is a Mn-Ni-based oxide. As a material of the resistance film 103, there is metal glaze (made by mixing and firing glass powder and ruthenium oxide powder). The electrode film 104 is formed by vacuum evaporation or sputtering. Ti as material
-There is Pt-Au. Since the LD chip is mounted on the electrode film 104 using solder, the step and the surface roughness due to the difference in thickness between the thermistor film 102 and the resistance film 103 are absorbed by the solder.

Here, examples of the resistance values and dimensions of the thermistor film 102 and the resistance film 103 and the resistivity of the material are shown. FIG.
Alternatively, the combined resistance of the thermistor 204 and the resistor 205 used in the LD driving method of FIG. 3 is 100Ω or less. This is LD20
It is determined by the characteristic of 1 and the voltage (Vcc) of the logic circuit 202.
Here, the calculation is made assuming that the combined resistance is 50Ω and the resistances of the thermistor film 102 and the resistance film 103 are both 100Ω (these are determined from the matching relationship with other circuit parts).
Assuming that the resistance of the film 103 is R, the resistivity is ρ, and the coefficient of the contribution of the shape to the resistance value (hereinafter, referred to as the shape factor of the resistor) is A,
9; R = A · ρ. The size of the upper surface of the LD carrier is 1.2m
m × 1.0 mm, and the areas of the thermistor film 102 and the resistance film 103 are halved. The film thickness is 10 μm. At this time, A
= 0.167. Then, R = 100 when ρ = 599 Ωcm.

In the above description, the thermistor film 102 and the resistance film 103 have the same shape and are formed on the entire upper surface of the LD carrier 101. However, by changing the area of the two films, a part of the upper surface of the LD carrier 101 can be formed. It is also possible to form a gap at the boundary between the two films. By changing the area, the resistance value can be adjusted without changing the thickness or the composition of the thermistor film 102 and the resistance film 103.
When a gap is formed at the boundary, an insulating film is preferably formed in advance on a portion of the upper surface of the LD carrier base 101 where the gap is formed.

In this embodiment, the thermistor film 102 and the resistance film 103
Is easy to fabricate because it can be formed by a thick film technique and its shape is simple. Further, the LD is connected to the thermistor film 10.
2 and stacked on the LD carrier via the resistive film 103 and the electrode film 104, the thermal resistance and the parasitic capacitance can be reduced, and the temperature compensation can be improved and the deterioration of the frequency characteristics can be reduced.

(Second Embodiment) Next, a second embodiment of the present invention will be described with reference to the drawings. FIG. 5 is a configuration diagram showing a top view and a front view of a second embodiment of the LD carrier of the present invention. The same components as those in the first embodiment shown in FIG. 1 are denoted by the same reference numerals. The difference is that the thermistor film 102 and the resistance film 103 are divided into stripes or strips and arranged alternately. Again, thermistor film
Since the thickness of 102 and the resistance film 103 is overwhelmingly small compared to their plane size, it is not necessary to care much whether they are in contact or not. 5, the thermistor film 102 (a plurality of thermistor films 102 are connected in parallel to form a composite thermistor) and the resistive film 10
Three parallel circuits (a plurality of resistance films 103 are connected in parallel to form a combined resistance) are connected to the LD.

In this embodiment, the distribution of the thermistor region and the resistance region is averaged. Thereby, the tolerance of the installation position of the LD chip on the LD carrier is further increased.

The area ratio of the thermistor film 102 and the resistive film 103 and the formation of the gap at the boundary are the same as in the first embodiment. L with an LD chip mounted on this LD carrier
The wiring of the D module is the same as in the first embodiment.

(Third Embodiment) Next, a third embodiment of the present invention will be described with reference to the drawings. FIG. 6 is a block diagram of a third embodiment of the LD carrier of the present invention. The same components as those of the first embodiment shown in FIG. 1 are denoted by the same reference numerals.
The difference is that the region of the resistive film 103 is formed in a lattice shape, and the thermistor film 102 is formed in the opening. Also here, since the thickness of the thermistor film 102 and the resistance film 103 is overwhelmingly smaller than their plane size, it is not necessary to care much whether they are in contact or not. 6, the thermistor film 102 (a plurality of thermistor films 102 are connected in parallel to form a combined thermistor) and a resistive film 103 (the lattice-like resistive film 103 as a whole forms a resistor in the thickness direction) Are connected to the LD.

In this embodiment, the distribution of the thermistor region and the resistance region is further averaged. Therefore, the tolerance of the installation position of the LD chip on the LD carrier is further increased.

The area ratio between the thermistor film and the resistive film and the formation of the gap at the boundary between them are the same as in the first embodiment.
The wiring of the LD module in which the LD chip is mounted on the LD carrier is the same as in the first embodiment. By modifying the present embodiment, the thermistor film 103 is formed in a lattice shape,
02 may be placed in the opening.

(Fourth Embodiment) Next, a fourth embodiment of the present invention will be described with reference to the drawings. FIG. 7 is a block diagram of a fourth embodiment of the LD carrier of the present invention. The components are the first
An insulating film 701 is added to FIG. 1, which is a configuration diagram of the embodiment. The electrode film 104 formed on the uppermost surface is formed in a partial region. The area is indicated by a dotted line in the top view.

The thermistor film 102 and the resistance film 103 have a comb shape and are formed by a thin film technique (vacuum deposition or sputtering). As shown in the top view of FIG. 7, the comb-type thermistor film 102 and the resistive film 103 have a structure in which the stem of the comb is on the conductive LD carrier base 101 and the teeth of the comb are engaged with each other with a gap. It is on the insulating film 701. The electrode film 104 is formed on an uneven surface formed by the comb-type thermistor film 102, the resistance film 103, and the insulating film 701, and both the thermistor film 102 and the resistance film 103 are very thin (for example, in the first embodiment). (In the example, it is 10 μm.) Therefore, the unevenness is absorbed by solder in mounting the LD chip. The material of the thermistor film 102 includes SiC and Ge. As a material of the resistance film 103, there is Ni-Cr or Ta-N. As a material of the insulating film 701,
There is SiO _{2 and} is formed on the conductive LD carrier base 101 by sputtering.

In the present embodiment, since the thermistor film 102 and the resistance film 103 adopt the above-described form, the current path is in the direction along the thermistor film 102 and the resistance film 103. Accordingly, the shape factor A of the resistance of the film can be significantly increased as compared with the above embodiment in which the current path is in the thickness direction of the thermistor film 102 and the resistance film 103. Further, the resistance value can be set by adjusting the width and number of the comb teeth.

Here, the thermistor film 10 in this embodiment is
2 shows an example of the shape of 2 and the resistance film 103, and the resistivity of the material. The resistance values of the thermistor film 102 and the resistance film 103 are both set to 100Ω, as in the first embodiment. In FIG. 7, the length a of the comb tooth is 0.2 mm, the width b of the comb tooth is 0.1 mm,
The number of teeth of the comb is four. In this case, the shape factor A = 5000
And the resistivity ρ = 0.02Ωcm.

In this embodiment, since the shape factor A can be easily adjusted, various resistance values can be realized, and since the thin film technology is used, the control accuracy of the shape, composition and film thickness is high. Also, the accuracy of the resistance value is high. L on this LD carrier
For wiring of LD module with D chip mounted,
This is the same as in the first embodiment.

Even if the thermistor film 102 and the resistance film 103 of the first embodiment or the second embodiment are formed on the LD carrier base 101 on which the insulating film 701 is formed, the current path is not changed. In addition, it is possible to realize an LD carrier in a direction along the film of the resistance film 103.

(Fifth Embodiment) Next, a fifth embodiment of the present invention will be described with reference to the drawings. FIG. 8 is a block diagram of a fifth embodiment of the LD carrier of the present invention. LD carrier base
Reference numeral 801 denotes an insulator, and gold plating 802 is applied to the side, bottom, and part of the top. Thermistor film 102 and resistance film 103
It has a comb shape, and its stem is in contact with the gold plating 802 at the edge of the LD mounting surface. The lower surface of the comb tooth portion is in contact with the LD mounting surface of the LD carrier 801, and the tip is in contact with the electrode film 104. In FIG. 8, the step shape at the edge of the electrode film 104 is exaggerated.
Since step 102 and resistive film 103 are both very thin, this step is L
It is sufficiently absorbed by the solder in the D chip mounting to be small.

The other points are the same as those of the fourth embodiment, and the effects of this embodiment are the same as those of the fourth embodiment. Again, the thermistor film 102 and the resistive film 103 of the first embodiment or the second embodiment are coated with the gold-plated 802 LD carrier base.
Even on the 801, it is possible to realize an LD carrier in which the current path is along the thermistor film 102 and the resistance film 103.

[0053]

As described above, according to the invention of the present application, a light emitting element suitable for a light emitting element driving method having a simple temperature compensation function in which a parallel circuit of a thermistor and a resistor is connected in series to the light emitting element. And a thermistor mounting form can be provided. Since no new wiring is generated, the high-frequency characteristics are not degraded, and the thermal resistance between the light emitting element and the thermistor is small, so that the performance of the temperature compensation function can be improved. Furthermore, it is also possible to reduce component costs and mounting costs.

[Brief description of the drawings]

FIG. 1 is a configuration diagram of a first embodiment of a light emitting device carrier of the present invention.

FIG. 2 is a circuit diagram of a first example of a light emitting element driving system to which the light emitting element carrier or the light emitting element of the present invention is applied.

FIG. 3 is a circuit diagram of a second example of a light emitting element driving system to which the light emitting element carrier or the light emitting element of the present invention is applied.

FIG. 4 is a configuration diagram of a light emitting element module to which the light emitting element carrier of the present invention is applied.

FIG. 5 is a configuration diagram of a light emitting element carrier according to a second embodiment of the present invention.

FIG. 6 is a configuration diagram of a third embodiment of the light emitting device carrier of the present invention.

FIG. 7 is a structural view of a light emitting element carrier according to a fourth embodiment of the present invention.

FIG. 8 is a structural view of a light emitting element carrier according to a fifth embodiment of the present invention.

FIG. 9 is a configuration diagram of a conventional example of the light emitting element carrier of FIG. 9;

[Explanation of symbols]

 101: LD carrier base (conductive) 102: Thermistor film 103: Resistive film 104: Electrode 201: LD 202: Logic circuit 203: Output stage transistor 204: Thermistor 205: Resistance 401: LD carrier 402: LD chip 403: Logic circuit IC chips 404, 405: bonding wire 406: LD module package 407: circuit board 408: optical mount 409: electrical connection terminal 410: optical fiber 701: insulating film 801: LD carrier base (insulator) 802: gold plating layer 901: heat sink 902: LD in conventional example 903: Thermistor thin film in conventional example

Claims (17)

[Claims] 1. A light emitting element carrier applied to a light emitting element driving method in which a parallel circuit of a thermistor having a negative temperature characteristic and a resistance element is connected in series to a current driven type light emitting element. The light emitting element carrier, wherein the thermistor and the resistance element are formed in a film shape on a surface of the base of the carrier on which the light emitting element is mounted. 2. The device according to claim 1, further comprising a conductive portion on the light emitting element mounting surface, wherein the thermistor and the resistor are formed in a film on the conductive portion.
The light-emitting element carrier according to item 1. 3. The light emitting device carrier according to claim 2, wherein each of said thermistor and said resistor is one rectangular or rectangular film. 4. The light emitting element carrier according to claim 2, wherein said thermistor and said resistance element are each a plurality of strip-shaped films and are formed alternately. 5. The method according to claim 2, wherein one of the thermistor and the resistance element is a lattice-like film, and the other is a plurality of films disposed in openings of the lattice-like film. The light-emitting element carrier according to the above. 6. The light emitting element mounting surface has a conductive region and an insulating region, and the thermistor and the resistive element film are formed over the two regions of the conductive region and the insulating region. 2. The light-emitting element carrier according to claim 1, wherein: 7. The light emitting element carrier according to claim 6, wherein said thermistor and said resistance element are each a comb-shaped film, a rectangular or rectangular film, or a plurality of strip films. 8. The light emitting device according to claim 6, wherein the light emitting element carrier base is made of a conductive material, and an insulating film is formed on a part of the light emitting element mounting surface. Element carrier. 9. The light emitting element carrier base according to claim 6, wherein the light emitting element carrier base is made of an insulating material, and a conductive film is formed on a part of the light emitting element mounting surface. Light emitting element carrier. 10. An electrode film is formed on a film of said thermistor and said resistance element.
10. The light-emitting element carrier according to any one of claims 9 to 9. 11. The light emitting device carrier according to claim 6, wherein an electrode film is formed on the thermistor, the film of the resistor, and the insulating region. 12. A light-emitting element module, wherein a light-emitting element is mounted on the light-emitting element mounting surface of the light-emitting element carrier according to claim 1. 13. The light emitting device module according to claim 12, wherein said light emitting device is an LD or an LED. 14. A light emitting device applied to a light emitting device driving method in which a parallel circuit of a thermistor having a negative temperature characteristic and a resistor is connected in series to a current driven type light emitting device. A light-emitting device, wherein the thermistor and the resistor are formed in a film on an electrode. 15. A light-emitting element driving method comprising: forming a light-emitting element module using the light-emitting element carrier according to claim 1; and using the light-emitting element module at a constant voltage. 16. A light emitting element driving method, wherein the light emitting element module according to claim 12 is used for constant voltage driving. 17. A light emitting element driving method, wherein the light emitting element according to claim 14 is used in constant voltage driving.