CN101604389A - A kind of fingerprint image of four fingers acquisition method and device - Google Patents

Abstract

The invention provides a kind of fingerprint image of four fingers acquisition method and device, Collection prism is arranged on the acquisition window place of collector body, Collection prism is the parallel hexahedron of upper and lower surface, upper surface is the fingerprint collecting face, be positioned at fingerprint collecting window place, lower surface is for gathering pilot lamp silk-screen face, the left side is silver-plated reflecting surface, the lower surface device of Collection prism has the infrared LED light source, catoptron, spectroscope, imaging lens, CMOS photoelectric commutator series arrangement is positioned on the systematic optical axis, catoptron is located between Collection prism and the imaging lens, and the light of Collection prism outgoing is reflexed on the imaging lens, and the CMOS photoelectric commutator is arranged on the image planes of imaging lens.The present invention utilizes the infrared light supply irradiation, has realized obtaining on the color cmos chip high-quality black white image; Adopt the scheme of CPLD cooperation high speed FIFO, reached the maximum transmission rate of USB interface.Simultaneously can gather four fingers, improve collecting efficiency greatly, also improve the precision of fingerprint recognition simultaneously.

Description

A kind of fingerprint image of four fingers acquisition method and device

Technical field

The present invention is a kind of fingerprint image of four fingers acquisition method, also discloses the fingerprint acquisition device that adapts with this method simultaneously, belongs to the fingerprint acquisition device technical field.

Background technology

Even refer in the optical system of fingerprint acquisition instrument in four of routine, generally be to adopt isosceles right-angle prism as the fingerprint collecting prism, adopt black and white CMOS electron device as sensor, because the volume and the black and white CMOS overall dimensions of isosceles right-angle prism are all very big, so that the body of Acquisition Instrument also just becomes is very big; In addition, refer to that even the data volume of fingerprint image is far longer than the data volume that collection singly refers to image owing to gather four, so most producers adopt FPGA to cooperate the connectivity scenario of biplate SDRSDRAM or monolithic DDR SDRAM, even also increased piece of CPLD on the basis in front and be placed between FPGA and the Sensor, be used for managing the sequential of Sensor, finally cause four on the market to refer to that the fingerprint acquisition instrument volume is all bigger, price is also very expensive, has restricted four and has referred to promoting the use of of fingerprint acquisition instrument.

Summary of the invention

The invention provides a kind of fingerprint image of four fingers acquisition method and device, overcome the existing shortcoming that fingerprint acquisition instrument volume of the same type is big, heavy, cost is high.

The present invention's four finger fingerprint acquisition instruments comprise with the lower part to be formed: by the infrared LED light source, Collection prism, catoptron, spectroscope, imaging lens, the CMOS photoelectric commutator, usb data line and collector body constitute, it is characterized in that: Collection prism is arranged on the acquisition window place of collector body, Collection prism is the parallel hexahedron of upper and lower surface, upper surface is little to be the fingerprint collecting face, be positioned at fingerprint collecting window place, lower surface is greatly gathered pilot lamp silk-screen face, the left side is silver-plated reflecting surface, with upper surface angle 70 degree, inclined-plane, right side and lower surface angle 40 degree, the lower surface of Collection prism 2 is about 3 millimeters and locates device the infrared LED light source is arranged, catoptron is about 25 millimeters apart from the Collection prism lower surface, and with horizontal direction angle 50 degree, catoptron, spectroscope, imaging lens, CMOS photoelectric commutator series arrangement is positioned on the systematic optical axis, catoptron is located between Collection prism and the imaging lens, the light of Collection prism outgoing is reflexed on the imaging lens, and the CMOS photoelectric commutator is arranged on the image planes of imaging lens.

Mirror surface plating spectro-film, wavelength is the visible transmission of 400-700nm, transmitance is greater than 85%; The while infrared light reflection, reflectivity is greater than 98%.

The CMOS photoelectric commutator mainly is made of USB control chip, programmable logic device (CPLD), color cmos chip and cache chip FIFO;

USB is connected RESET_BAR_IN signal, START signal, IFCLK signal, INT1 signal, FLAGC signal and SLWR signal by the IO port with the IO port of CPLD, the FPDP DATA_USB of USB is also connecting the IO port of CPLD; The USB control chip is connected with the color cmos chip by the I2C port, and the USB control chip is configured the color cmos chip by the I2C port;

The CPLD chip is transferred to the color cmos chip by output port with RESET_BAR signal and EXTCLK signal, and color cmos is resetted; Row signal LV, field signal FV, data sync clock signal PCLK are connected with the input port of CPLD with view data DATA_SENSOR;

CPLD is connected with WRST signal, WE signal, WCK signal, RRST signal, RE signal, RCK signal, ORDY signal, IN_USB data, the OUT_BUS data of FIFO by the IO port, and the view data IN_USB that color cmos is transmitted is written among the FIFO and keeps in; Give CPLD with the view data of storing among the FIFO by the OUT_BUS port transmission, CPLD gives the USB control chip by the DATA_USB port with image data transmission again.

After Acquisition Instrument powered on, infrared LED light source sign was bright, and the expression light source is operate as normal; When sign was bright, the user need refer to left hand four to be placed on to carry out image acquisition on the collection face; When sign was bright, the user need be placed on two thumbs the center of collection face and carry out image acquisition; When sign was bright, the user need refer to the right hand four to be placed on to carry out image acquisition on the collection face; Fingerprint signal by how on collection face enters the color cmos chip through light path, on the CMOS photoelectric commutator, at first the USB control chip is configured, and makes it be operated in bulk transfer mode; Needed signal when next the USB control chip offers CPLD, external FIFO, color cmos chip operation by IO; The USB control chip is provided with the color cmos chip register by the I2C interface then, comprises that setting completed to the setting of information such as acquisition window size, acquisition window starting point, time shutter, gain, and the color cmos chip is started working; The signal that CPLD provides by the color cmos chip is input to the view data of color cmos chip and carries out buffer memory among the external FIFO, the status signal that provides of status signal that provides by the USB control chip and external FIFO to host computer, shows complete fingerprint image of four fingers through relevant treatment such as the splicing of upper computer software, adjustment with the image data transmission among the external FIFO again.

This Acquisition Instrument can be gathered four fingers simultaneously, has improved collecting efficiency greatly, has also improved the precision of fingerprint recognition simultaneously; The present invention realizes the mode of operation indication at the lower surface silk-screen sign of Collection prism by blue-ray LED under it and sheen film.Indicating effect is attractive in appearance, generous, and is buried in the glass bottom, has high-tech mystique.

Good effect of the present invention is: utilize the infrared light supply irradiation, realized obtaining high-quality black white image on the color cmos chip.Adopt the scheme of CPLD cooperation high speed FIFO, reached the maximum transmission rate of USB interface.

Collection prism of the present invention adopts the parallel characteristics of optical surface up and down, and generation 2 secondary reflections in Collection prism are for the first time to reflect at plating internal reflection face, is for the second time that light is in the inner generation of prism total reflection.2 secondary reflections have effectively reduced the volume of instrument, mirror surface plating spectro-film, and wavelength is the visible transmission of 400-700nm, transmitance is greater than 85%; The while infrared light reflection, reflectivity is greater than 98%.Wait status indicator in the silk-screen operation indication of Collection prism bottom, realize the mode of operation indication by blue-ray LED under it and sheen film.Indicating effect is attractive in appearance, generous, and is buried in the glass bottom, has high-tech mystique.Ingenious part of the present invention is: removed the influence of the blue light of pilot lamp for imaging optical path by infrared selective reflecting mirror and spectroscope, had the advantage easy, with low cost, that effect is magical of producing;

Infrared selective reflecting mirror has been used present top multicoating technology, nearly 50 layers of coating layers, and when infrared reflectivity was brought up to 98%, the transmitance of visible light still was higher than 95%.This is a big technological breakthrough at optical field, and this technology is applied in four and refers to make instrument particularly outstanding in like product to the antijamming capability of surround lighting in the Acquisition Instrument.

The camera lens front end increases the spectroscope of infrared permeation, visible light reflection, when having guaranteed that light path makes full use of infrared light, parasitic light with visible light wave range carries out filtering again, with being used in combination of infrared selective reflecting mirror, has further reduced the interference of surround lighting to Acquisition Instrument.

Description of drawings

Fig. 1 is an optical system schematic diagram of the present invention;

Fig. 2 is a Collection prism front view of the present invention;

Fig. 3 is a Collection prism left view of the present invention;

Fig. 4 is a Collection prism vertical view of the present invention

Fig. 5 is circuit theory diagrams of the present invention;

Fig. 6 is imprinted on the sign silk-screen synoptic diagram of Collection prism bottom for the present invention;

Among the figure, 1, the infrared LED light source; 2, Collection prism; 3, catoptron; 4, spectroscope; 5, imaging lens; 6, CMOS photoelectric commutator; 7, usb data line; 8, Acquisition Instrument body; 9, infrared LED light source sign; 10, gather the sign that left hand four refers to; 11, gather the sign of two thumbs; 12, gather right four signs that refer to.

Embodiment

Embodiment 1

According to shown in Figure 1, form the fingerprint image of four fingers Acquisition Instrument by infrared LED light source (1), Collection prism (2), catoptron (3), spectroscope (4), imaging lens (5), CMOS photoelectric commutator (6), usb data line (7), Acquisition Instrument body (8).Wherein, infrared LED light source (1) is about 3 millimeters places as the lower surface that the lighting device of system is fixed on Collection prism (2); Catoptron (3) is fixed on Collection prism (2) lower surface and is about on 25 millimeters positions, being centered close on the systematic optical axis of catoptron (3), spectroscope (4), imaging lens (5), CMOS photoelectric commutator (6), spectroscope (4) is fixed on imaging lens (5) front, plays the filtering environmental light action.Infrared LED light source (1), catoptron (3) and spectroscope (4) make optical system avoid the influence of surround lighting to the full extent in conjunction with using.

Shown in Fig. 2,3,4, Collection prism (2) is the parallel hexahedron of upper and lower surface, upper surface is little to be positioned at fingerprint collecting window place for the fingerprint collecting face, the left side is silver-plated reflecting surface, with upper surface angle 70 degree, the inclined-plane, right side is spent with lower surface angle 40, at Collection prism (2) lower surface silk-screen four signs, as shown in Figure 6, the corresponding positions of infrared LED circuit of light sources plate is equipped with blue led and throws light on to sign.

As shown in Figure 5, circuit of the present invention mainly is made of USB control chip, programmable logic device (CPLD), color cmos chip and cache chip FIFO.Wherein the USB control chip is mainly realized the configuration to the color cmos chip, and gives computing machine with image data transmission; The transmission that programmable logic device (CPLD) major control view data is complete; The color cmos chip is mainly realized the collection of image; Cache chip FIFO mainly realizes the temporary transient storage of view data.

USB is connected RESET_BAR_IN signal, START signal, IFCLK signal, INT1 signal, FLAGC signal and SLWR signal by the IO port with the IO port of CPLD, the FPDP DATA_USB of USB is also connecting the IO port of CPLD.Wherein the RESET_BAR_IN signal is a color cmos chip operate as normal reset signal before, the START signal is the commencing signal that starts CPLD work, the IFCLK signal is the clock signal that the USB chip provides, the INT1 signal is the external interrupt signal of USB, the FLAGC signal is the Status Flag signal that USB provides, controlling the transmission of data according to this Status Flag signal CPLD, SLWR is the enable signal of USB chip data transmission, situation when the USB permission, CPLD enables the SLWR signal, and gives the USB control chip with view data by the DATA_USB port transmission.

The USB control chip is connected with the color cmos chip by the I2C port, and the USB control chip is configured the color cmos chip by the I2C port, comprises the setting to information such as acquisition window size, acquisition window starting point, time shutter, gains.

The CPLD chip is transferred to the color cmos chip by output port with RESET_BAR signal and EXTCLK signal, wherein the RESET_BAR signal is the color cmos chip reset signal that USB provides, why pass through the CPLD chip, be because the RESET_BAR_IN signal voltage of USB output is 3.3V, and the working signal voltage of color cmos chip is 1.8V, so the RESET_BAR signal of the RESET_BAR_IN signal of 3.3V being reduced to 1.8V by the CPLD chip resets to the color cmos chip; The EXTCLK signal is the input clock signal of color cmos chip, is that CPLD is by step-down gets to the IFCLK signal.When color cmos chip operate as normal, row signal LV, field signal FV, data sync clock signal PCLK are connected with the input port of CPLD with view data DATA_SENSOR.

CPLD is connected with WRST signal, WE signal, WCK signal, RRST signal, RE signal, RCK signal, ORDY signal, IN_USB data, the OUT_BUS data of FIFO by the IO port.Wherein WRST signal and RRST signal are that CPLD is transferred to the write address reset signal of fifo chip and reads address reset signal; The WE signal is the enable signal of writing of FIFO, and when the WE signal was effective, CPLD was controlling the view data IN_USB that the color cmos chip is transmitted and is being written among the FIFO and keeps in; WCK is the write clock signal of FIFO, and the data that whenever are written among the FIFO all are synchronized with WCK; The RE signal is the enable signal of reading of FIFO, RCK is the read clock signal of FIFO, ORDY is the status signal that FIFO provides, when conditions permit, CPLD enables the RE signal, and the view data of storing among the FIFO is passed through the OUT_BUS port transmission give CPLD, CPLD gives the USB control chip by the DATA_USB port with image data transmission again.

Claims (3)

1, a kind of four even refer to fingerprint acquisition instrument, by infrared LED light source (1), Collection prism (2), catoptron (3), spectroscope (4), imaging lens (5), CMOS photoelectric commutator (6), usb data line (7) and collector body (8) constitute, it is characterized in that: Collection prism (2) is arranged on the acquisition window place of collector body (8), Collection prism (2) is the parallel hexahedron of upper and lower surface, upper surface is little to be the fingerprint collecting face, be positioned at fingerprint collecting window place, lower surface is greatly gathered pilot lamp silk-screen face, the left side is silver-plated reflecting surface, with upper surface angle 70 degree, inclined-plane, right side and lower surface angle 40 degree, the lower surface device of Collection prism 2 has infrared LED light source (1), catoptron (3) is located on Collection prism (2) lower surface position, and with horizontal direction angle 50 degree, catoptron (3), spectroscope (4), imaging lens (5), CMOS photoelectric commutator (6) series arrangement is positioned on the systematic optical axis, catoptron (3) is located between Collection prism (2) and the imaging lens (5), the light of Collection prism (2) outgoing is reflexed on the imaging lens (5), and CMOS photoelectric commutator (6) is arranged on the image planes of imaging lens (5).

2, the described Acquisition Instrument of claim 1 is characterized in that: catoptron (3) surface plating spectro-film, and wavelength is the visible transmission of 400-700nm, transmitance is greater than 85%; The while infrared light reflection, reflectivity is greater than 98%.

3, claim 1 or 2 described Acquisition Instruments, it is characterized in that: CMOS photoelectric commutator (6) mainly is made of USB control chip, programmable logic device (CPLD), color cmos chip and cache chip FIFO;

USB is connected RESET_BAR_IN signal, START signal, IFCLK signal, INT1 signal, FLAGC signal and SLWR signal by the IO port with the IO port of CPLD, the FPDP DATA_USB of USB is connected with the IO port of CPLD; The USB control chip is connected with the color cmos chip by the I2C port, and the USB control chip connects the color cmos chip by the I2C port;

The CPLD chip is transferred to the color cmos chip by output port with RESET_BAR signal and EXTCLK signal, and color cmos is resetted; Row signal LV, field signal FV, data sync clock signal PCLK are connected with the input port of CPLD with view data DATA_SENSOR;

CPLD is connected with WRST signal, WE signal, WCK signal, RRST signal, RE signal, RCK signal, ORDY signal, IN_USB data, the OUT_BUS data of FIFO by the IO port, and the view data IN_USB that color cmos is transmitted is written among the FIFO and keeps in; Give CPLD with the view data of storing among the FIFO by the OUT_BUS port transmission, CPLD gives the USB control chip by the DATA_USB port with image data transmission again.

Images