Miniaturized laser ignition SiP module

Abstract

The invention relates to a miniaturized laser ignition SiP module, which comprises electrode pins, a circuit substrate, a laser chip, a detector chip, a focusing lens group, a security switch, an ignition window, a packaging shell and a functional circuit, and is characterized in that a bonding pad is arranged on the circuit substrate, and a plurality of layers of metal wires are printed on the circuit substrate and are used for welding the laser chip, the detector chip and the functional circuit; the circuit substrate is fixed in the packaging shell, and overall airtightness is achieved through seal welding. When the ignition SiP module works, an external circuit signal is transmitted into the functional circuit through the electrode pins, the functional circuit controls the laser chip, the detector chip and the security switch, the laser chip outputs laser, the detector chip feeds back and outputs laser power, the focusing lens group focuses the laser, and the laser is output from the ignition window through the security switch to complete ignition. Based on the SIP technology, devices are assembled on the front layer and the back layer of the circuit substrate to achieve the laser ignition module, the size of an existing ignition module is greatly reduced, and an efficient and compact laser ignition solution is provided.

Description

Technical Field

[0001] The invention belongs to the technical field of laser ignition, and in particular relates to a miniaturized laser ignition SiP module. Background Art

[0002] Traditional electric ignition technology uses the heat generated by a thermal resistor to ignite the explosive, which has problems such as static discharge, electromagnetic radiation, and explosive corrosion of the thermal resistor. The static electricity generated by electric ignition equipment during production, storage, and use has become a major hidden danger affecting the safety of electric ignition. In order to make the ignition system safer, the ignition technology needs to be transformed from sensitive ignition technology to insensitive ignition technology.

[0003] Laser ignition technology uses laser energy to convert into heat energy to ignite the gunpowder. Compared with electric ignition technology, it has good anti-electromagnetic and anti-static interference capabilities and safety. First of all, in terms of system architecture, the use of laser directly acts on the agent to avoid direct contact between energetic materials and electronic systems, fundamentally eliminating the impact of static electricity and electromagnetic interference, and greatly improving the ignition technology's ability to resist electromagnetic radiation. Secondly, the laser ignition system can be designed as an in-line ignition system. A security switch can be added to this type of system. The security switch can not only prevent static electricity from damaging the laser, but also avoid accidental ignition of the system, thereby improving the safety of the ignition system.

[0004] The existing laser ignition technology uses a separate design for the detonator, control, monitoring and security modules. After the energy is transmitted to the detonator through the optical fiber, it acts on the agent to complete the ignition. This type of design causes a large loss of laser output energy during coupling to the optical fiber and transmission. Secondly, the overall system size is large, and a separate space is required to place the control and monitoring modules, which is not conducive to use in environments with strict space weight restrictions such as satellites and aerospace. Summary of the invention

[0005] The purpose of the present invention is to provide a miniaturized laser ignition SiP module, which adopts the method of assembling components on the front and back of the circuit substrate to realize three-dimensional stacking packaging technology, and integrates the traditional separate detonator, control, feedback, security module circuit and energy transmission path. The size of the existing laser ignition module is greatly reduced, and an efficient and compact laser ignition solution is provided.

[0006] The above-mentioned purpose of the present invention is mainly achieved through the following technical solutions:

[0007] A miniaturized laser ignition SiP module comprises electrode pins, a circuit substrate, a laser chip, a detector chip, a focusing lens group, a safety switch, an ignition window, a packaging shell and a functional circuit. The circuit substrate, the laser chip, the detector chip, the focusing lens group, the safety switch and the functional circuit are arranged in the packaging shell, the packaging shell is provided with an ignition window, the electrode pins penetrate the packaging shell and are used to connect an external circuit and the functional circuit, the laser chip and the detector chip are arranged on the circuit substrate, when the ignition SiP module is working, the external circuit signal is transmitted to the functional circuit through the electrode pins, the functional circuit controls the laser chip, the detector chip and the safety switch, the laser chip outputs laser, the detector chip feeds back the output laser power, the focusing lens group focuses the laser, and the laser is output from the ignition window through the safety switch to complete the ignition.

[0008] The packaging shell includes a metal cover and a metal dam. The outer circle of the metal cover is an annular metal structure, and the inner circle is a ceramic plate. The electrode pins are arranged on the ceramic plate. The ignition window is arranged on the metal dam on the opposite side of the metal cover.

[0009] The metal cover and the metal dam are integrally assembled by sealing welding, and the metal cover and the metal dam are made of stainless steel 13Cr11 Ni2W2MoV.

[0010] Before the metal cover and the metal dam are assembled and sealed to achieve overall airtight packaging, heat treatment and nitrogen filling processes are used to release water vapor and oxygen to delay oxidation of components and solder joints.

[0011] The focusing lens group and the safety switch are fixed on the circuit substrate by gluing or welding, and the ignition window is fixed on the metal dam by laser welding. The inner wall of the metal dam is provided with a supporting structure for fixing the circuit substrate.

[0012] The functional circuit includes a drive control circuit, a current amplifying circuit, a safety switch control circuit and a power management circuit. The drive control circuit is connected to an external circuit through electrode pins, and is used to input an external ignition signal to drive the laser chip to output laser; the current amplifying circuit of the detector chip is connected to an external circuit through electrode pins, and is used to amplify the current generated by the detector chip and convert it into a voltage signal output to feedback the output laser power of the laser chip; the safety switch control circuit is connected to an external circuit through electrode pins, and is used to input an external security control signal to control the opening and closing of the safety switch to control whether the laser beam can pass through the safety switch; the power management circuit is used to convert the input power signal into a specific voltage to power the laser chip, the detector chip and the safety switch respectively.

[0013] A light hole is provided on the safety switch, and the safety switch controls whether the laser beam can pass through by controlling the opening and closing of the light hole; the center of the laser output surface of the laser chip, the center of the focusing lens group, the center of the light hole of the safety switch and the center of the ignition window are on the same straight line.

[0014] The ignition window material is a mica sheet, a sapphire glass sheet, a quartz glass sheet, a K9 glass sheet or a celluloid sheet, preferably a sapphire glass sheet.

[0015] The light hole is circular with a diameter of 0.5-0.7mm, and the ignition window is circular with a diameter of 1-2mm.

[0016] The laser output from the laser chip is focused by the focusing lens group and then output from the ignition window. The distance between the focusing point of the output laser spot and the ignition window is 1-3mm.

[0017] The circuit substrate is a ceramic substrate, the circuit substrate is a single-layer or multi-layer substrate, and the device is arranged on the front side or the back side of the circuit substrate.

[0018] Compared with the prior art, the present invention has at least the following beneficial effects:

[0019] (1) The laser ignition SiP module of the present invention adopts integrated packaging technology to achieve miniaturized integration of various components. Based on the HTCC ceramic substrate and metal shell packaging process, it integrates lasers, control drive circuits, micromechanical components and optical components, simplifies the system structure, improves integration, greatly reduces the system volume, and is suitable for application scenarios with strict volume space restrictions.

[0020] (2) The present invention integrates the laser chip with the drive control circuit and the spatial optical component, which reduces the transmission path and achieves low loss and high performance output of the system.

[0021] (3) Compared with the traditional high-voltage pulse ignition, the present invention is easier to realize the ignition of the sudden explosive, avoids the use of sensitive detonating agents, and improves the safety of the system during production and transportation. BRIEF DESCRIPTION OF THE DRAWINGS

[0022] Figure 1 This is a schematic diagram of the principle of the laser ignition SiP module of the present invention;

[0023] Figure 2 This is a schematic diagram of the laser ignition SiP module of the present invention. DETAILED DESCRIPTION

[0024] The present invention is further described in detail below with reference to the accompanying drawings and specific embodiments:

[0025] Figure 1The figure shows the schematic diagram of the laser ignition SiP module. The laser ignition SiP module includes a control circuit, a management circuit, an ignition laser, a photodetector, a lens assembly, an ignition window and a safety switch. The control circuit includes an ignition laser drive control circuit, a photodetector amplification circuit and a safety switch control circuit. The power management circuit is connected to the external power signal to convert the external voltage into voltages of different amplitudes as the power input for other functional circuits.

[0026] The ignition laser drive control circuit is connected to the external circuit through electrode pins to input the external ignition signal and drive the ignition laser to output laser; the photodetector amplifier circuit is also connected to the external circuit through electrode pins to amplify the weak current generated by the photodetector and convert it into a voltage signal output to feedback the luminous power of the ignition laser; the safety switch control circuit is connected to the external circuit through electrode pins to input the external security control signal and drive the opening and closing of the safety switch to control whether the laser beam can pass through the safety switch.

[0027] like Figure 2 As shown, a miniaturized and highly integrated laser ignition SIP module includes electrode pins 1, a circuit substrate 2, a laser chip 3, a detector chip 4, a focusing lens group 5, a safety switch 6, an ignition window 7, a packaging shell and a functional circuit.

[0028] The circuit substrate 2 is printed with pads and multi-layer metal wires, and the electrical interconnection of electronic components and functional circuits is realized by welding or wire bonding, including the laser chip 3 and the drive control circuit A, the detector chip 4 and the current amplifier circuit B, the security switch control circuit C and the power management circuit D. The drive control circuit A is connected to the external circuit through the electrode pin 1 to input the external ignition signal and drive the laser chip 3 to output the laser; the current amplifier circuit B of the detector chip 4 is connected to the external circuit through the electrode pin 1 to amplify the weak current generated by the detector chip 4 and convert it into a voltage signal output to feedback the output optical power of the ignition laser; the security switch control circuit C is connected to the external circuit through the electrode pin 1 to input the external security control signal and drive the security switch 6 to open and close to control whether the laser beam can pass through the security switch; the power management circuit D is used to convert the power signal with an input voltage of 25-35V into a specific voltage to supply power to the laser chip 3, the detector chip 4 and the security switch 6 respectively.

[0029] Electronic components and functional circuits are preferably bare chips to generate high-power, stable laser output, which is convenient for miniaturization and integration. The laser chip 3 uses a VCSEL laser chip with a wavelength of 980nm (the sensitive wavelength of the drug) and a continuous output power greater than 5W to improve ignition efficiency.

[0030] The packaging shell is composed of a metal cover 11 with electrode pins and a metal dam 12 with an opening on one side and an optical window 7 encapsulated on the other side, wherein the metal cover 11 is a metal structure with an outer circle and an embedded ceramic plate 10, and there are circuit lines inside the ceramic plate to achieve left and right interconnection, and to lead the input and output signals on the internal circuit substrate 2 to the external electrode pin 1; the inner wall of the metal dam 12 has a supporting structure for fixing the circuit substrate 2, and the metal cover 11 and the metal dam 12 are integrally packaged by laser sealing.

[0031] The metal dam 12 and the metal cover 11 are designed to be cylindrical and made of alloy materials such as stainless steel 13Cr11 Ni2W2MoV.

[0032] Electrode pin 1 mainly includes three functions: power input, control signal input and feedback signal output. A total of 5 pins are designed, namely power input pin, ground pin, safety switch control signal input pin, ignition signal input pin and feedback signal output pin. Among them, the power input pin and ground pin are external 25-35V power signal input pins; the safety switch control signal pin is an external security control signal input pin to control the opening and closing of the safety switch 6; the ignition signal input pin is an external ignition control signal input pin to control the laser chip 3 to output laser; the feedback signal output pin is the internal photodetector circuit voltage feedback signal output pin to feedback the real-time output power size of the laser chip 3.

[0033] The focusing lens group 5 and the safety switch 6 are aligned with the laser chip 3 by gluing or welding and fixed on the circuit substrate 2. The ignition window 7 is fixed on the metal dam 12 by welding to ensure that the ignition window 7, the light hole h, the focusing lens group 5 and the center of the light-emitting surface f of the laser chip 3 are on the same horizontal line to ensure that the light path is unobstructed.

[0034] The safety switch 6 is a micro-electromechanical switch, and the light hole h is opened and closed by the control circuit of the safety switch 6, so as to achieve the purpose of controlling the laser beam.

[0035] The material of the ignition window 7 is required to have good light transmittance and good compatibility with the ignition agent. Mica sheets, sapphire glass sheets, quartz glass sheets, k9 glass sheets, celluloid sheets, and other optical windows with good light transmittance and low power loss can be selected. As a preferred method, sapphire glass sheets are selected as the light window.

[0036] By adopting SiP packaging technology, the electronic components, functional circuits and optical components are assembled and fixed in the metal dam 12, and the metal cover 11 and the metal dam 12 are welded and sealed by laser welding to form a miniaturized and highly integrated laser ignition module.

[0037] Before the metal dam 12 and the metal cover 11 are assembled and sealed to achieve overall airtight packaging, heat treatment and nitrogen filling processes are preferably used to release water vapor and oxygen to delay oxidation of components and solder joints and extend the life of the module.

[0038] The focusing lens group 5 is composed of two lenses and is fixed on the circuit substrate 2 by welding.

[0039] The safety switch 6 is a MEMS switch, and the opening and closing of the light hole h is realized by the control circuit of the safety switch 6. The light hole h is circular with a diameter of 0.5-0.7 mm, preferably 0.6 mm.

[0040] The ignition window 7 is circular in shape, with a diameter of 1-2 mm, preferably 1 mm, and is fixed to the metal dam 12 by laser welding.

[0041] Adjust the light beam so that the smallest spot is focused in the reagent chamber. At this time, the distance between the spot focus point and the ignition window 7 is maintained at 1-3 mm, preferably 1 mm. The laser continues to irradiate the reagent chamber to form an ignition point and complete the ignition.

[0042] The above description is only the best specific implementation mode of the present invention, but the protection scope of the present invention is not limited thereto. Any changes or substitutions that can be easily thought of by any technician familiar with the technical field within the technical scope disclosed by the present invention should be covered within the protection scope of the present invention.

[0043] The contents not described in detail in the specification of the present invention belong to the common knowledge of the professionals in this field.

Claims

1. A miniaturized laser ignition SiP module, characterized in that: The invention comprises electrode pins (1), a circuit substrate (2), a laser chip (3), a detector chip (4), a focusing lens group (5), a safety switch (6), an ignition window (7), a packaging shell and a functional circuit. The circuit substrate (2), the laser chip (3), the detector chip (4), the focusing lens group (5), the safety switch (6) and the functional circuit are arranged in the packaging shell. The packaging shell is provided with an ignition window (7). The electrode pins (1) penetrate the packaging shell and are used to connect an external circuit and a functional circuit. The laser chip (3) and the detector chip (4) are arranged on the circuit substrate (2). When the ignition SiP module is working, an external circuit signal is transmitted to the functional circuit through the electrode pins (1). The functional circuit controls the laser chip (3), the detector chip (4) and the safety switch (6). The laser chip (3) outputs laser light. The detector chip (4) feeds back the output laser power. The focusing lens group (5) focuses the laser light. The laser light is output from the ignition window (7) through the safety switch (6) to complete ignition.

2. A miniaturized laser ignition SiP module according to claim 1, characterized in that: The packaging shell comprises a metal cover (11) and a metal dam (12); the outer ring of the metal cover (11) is an annular metal structure, the inner ring is a ceramic plate (10), and the electrode pins (1) are arranged on the ceramic plate (10); the ignition window (7) is opened on the metal dam (12) on the opposite side of the metal cover (11).

3. A miniaturized laser ignition SiP module according to claim 2, characterized in that: The metal cover (11) and the metal dam (12) are integrally assembled by sealing and welding, and the metal cover (11) and the metal dam (12) are made of stainless steel 13Cr11 Ni2W2MoV.

4. A miniaturized laser ignition SiP module according to claim 3, characterized in that: Before the metal cover (11) and the metal dam (12) are assembled and sealed to achieve overall airtight packaging, heat treatment and nitrogen filling processes are used to release water vapor and oxygen to delay oxidation of components and solder joints.

5. A miniaturized laser ignition SiP module according to claim 2, characterized in that: The focusing lens group (5) and the safety switch (6) are fixed on the circuit substrate (2) by gluing or welding, and the ignition window (7) is fixed on the metal dam (12) by laser welding. The inner wall of the metal dam (12) has a supporting structure for fixing the circuit substrate (2).

6. A miniaturized laser ignition SiP module according to claim 1, characterized in that: The functional circuit comprises a driving control circuit (A), a current amplifying circuit (B), a safety switch control circuit (C) and a power management circuit (D). The driving control circuit (A) is connected to an external circuit via an electrode pin (1) and is used to input an external ignition signal to drive the laser chip (3) to output laser light. The current amplifying circuit (B) of the detector chip (4) is connected to an external circuit via an electrode pin (1) and is used to amplify the current generated by the detector chip (4) and convert it into a voltage signal output to feed back the output laser power of the laser chip (3). The safety switch control circuit (C) is connected to an external circuit via an electrode pin (1) and is used to input an external security control signal to control the opening and closing of the safety switch (6) to control whether the laser beam can pass through the safety switch. The power management circuit (D) is used to convert the input power signal into a specific voltage to supply power to the laser chip (3), the detector chip (4) and the safety switch (6) respectively.

7. The miniaturized laser ignition SiP module according to claim 1, characterized in that: The safety switch (6) is provided with a light-through hole, and the safety switch (6) controls whether the laser beam can pass through by controlling the opening and closing of the light-through hole; the center of the laser emission surface (f) of the laser chip (3), the center of the focusing lens group (5), the center of the light-through hole (h) of the safety switch (6) and the center of the ignition window (7) are on the same straight line.

8. The miniaturized laser ignition SiP module according to claim 1, characterized in that: The material of the ignition window (7) is a mica sheet, a sapphire glass sheet, a quartz glass sheet, a K9 glass sheet or a celluloid sheet, preferably a sapphire glass sheet.

9. The miniaturized laser ignition SiP module according to claim 1, characterized in that: The light-through hole is circular with a diameter of 0.5-0.7 mm, and the ignition window (7) is circular with a diameter of 1-2 mm.

10. The miniaturized laser ignition SiP module according to claim 1, characterized in that: The laser output from the laser chip (3) is focused by a focusing lens group (5) and then output from an ignition window (7), and the distance between the focus point of the output laser spot and the ignition window (7) is 1-3 mm.

11. The miniaturized laser ignition SiP module according to claim 1, characterized in that: The circuit substrate (2) is a ceramic substrate, the circuit substrate (2) is a single-layer or multi-layer substrate, and the device is arranged on the front side or the back side of the circuit substrate (2).

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