TWI387738B - Measurement board and apparatus with the same for measuring modulation transfer function value - Google Patents

Description

Modulation transfer function value measuring plate and measuring device using the measuring plate

The invention relates to a modulation transfer function value measuring board and a measuring device using the measuring board, in particular to a measuring device for a lens modulation transfer function value.

Modulation Transfer Function (MTF) value is a parameter for comprehensive evaluation of the sharpness, contrast and resolution of the lens. For the optical industry, it is often necessary to measure the MTF value of the lens.

The lens modulation transfer function value measuring device generally includes a test board, a modulation transfer function value measuring plate to which an image sensor is fixed, and a driving unit. The test board has a test pattern. The image sensor is configured to sense imaging of the test pattern on the test board via the lens to be tested on the image sensor. The driving unit is configured to drive the lens to be tested to move along the optical axis direction of the lens to be tested between the test board and the modulation transfer function value measuring plate, so that the test pattern on the test board is in the image The best imaging is formed on the sensor. In the measurement, generally after obtaining the optimal imaging on the image sensor, the modulation transfer function value of the test lens to be tested is calculated from the intensity value of the test pattern imaging brightness sensed by the pixel of the image sensor.

However, since the distance between the image sensor and the lens to be tested is usually small during the measurement process, especially when measuring a lens in a small electronic product such as a mobile phone or a digital camera, the lens often hits the image. The phenomenon of the detector, if the drive unit does not stop immediately after the impact, it will cause Serious damage to image sensors, lenses, and drive units.

In view of the above, it is necessary to provide a modulation transfer function value measuring plate capable of detecting an impact, and a modulation transfer function value measuring device using the measuring plate, so as to avoid the impact of the measuring device and the lens to be tested. damage.

A modulation transfer function value measuring plate capable of detecting an impact and a modulation transfer function value measuring device using the measuring plate will be described below by way of specific embodiments.

A modulation transfer function value measuring board includes a substrate, an image sensor fixed on the substrate, and a vibration sensor mounted on the substrate, the vibration sensor is configured to sense the The vibration of the substrate.

And a modulation transfer function value measuring device for measuring a modulation transfer function value of the lens to be tested, comprising a test board, a modulation transfer function value measuring board, and a driving unit. The test board has a test pattern. The modulation transfer function value measuring board includes a substrate, an image sensor fixed on the substrate, and a vibration sensor mounted on the substrate, the image sensor is used for sensing The test pattern on the test board is imaged on the image sensor via the lens to be tested, and the vibration sensor is used to sense the vibration of the substrate. The driving unit is configured to cause a relative movement between the lens to be tested and the modulation transfer function value measuring plate along the optical axis direction of the lens to be tested, when the lens to be tested collides with the image sensor, The shock sensor is capable of sensing the vibration of the substrate and generating a control signal to stop the drive unit from operating.

Compared with the prior art, the modulation transfer function value measuring board includes a vibration sensor mounted on the substrate, which can sense the vibration of the substrate, because the image sensor is fixed to the image sensor On the substrate, the vibration sensor can simultaneously sense the vibration of the image sensor. The modulation transfer function value measuring device using the measuring plate, wherein when the modulation transfer function value of the lens to be tested is measured, the driving unit causes the measuring lens and the modulation transfer function value measuring plate to be along the to-be-tested Relatively moving the optical axis direction of the lens, so that the test pattern on the test board is optimally imaged on the image sensor, when the lens to be tested collides with the image sensor, The vibration sensor can sense the vibration of the image sensor and the modulation transfer function value measuring board substrate, and the vibration sensor can generate a control signal to stop the driving unit immediately, thereby Serious damage to the measuring device and the lens to be tested can be avoided.

The embodiments of the present invention will be further described in detail below with reference to the accompanying drawings.

Referring to FIG. 1, a modulation transfer function value measuring plate 100 according to a first embodiment of the present invention includes a substrate 110, an image sensor 120 fixed on the substrate 110, and a substrate mounted on the substrate. Vibration sensor 130 on 110.

The image sensor 120 can be a charge coupled image sensor or a complementary metal oxide semiconductor image sensor.

The vibration sensor 130 can be a mercury resistive vibration sensor. The mercury resistive vibration sensor can sense whether the substrate 110 is vibrated according to a change in its resistance value. Of course, the vibration sensor 130 can also be a ball vibration switch or a reed switch.

The modulation transfer function value measuring plate 100 further includes a supporting device 140 for supporting the substrate 110. The support device 140 includes a base 142, a main body 144, a first magnetic collar 141 slidably coupled to the base 142, a second magnetic collar 143 and a third magnetic collar 145. The second and third magnetic collars 143 and 145 are fixedly connected to the base 142 and are disposed on opposite sides of the first magnetic collar 141. The main body 144 passes through the second, first and third magnetic collars 143, 141 and 145 in sequence and is fixedly connected to the first magnetic collar 141. One end 1442 of the main body 144 is a free end, and the other end 1444 is fixedly connected to the substrate 110 of the modulation transfer function value measuring board 100. The body 144 is maintained in an equilibrium position by the magnetic force between the first, second and third magnetic collars 141, 143 and 145.

The base 142 is generally provided with a guide rail 1422 at a position relative to the first magnetic collar 141. Preferably, the first magnetic collar 141 is movably connected to the guide rail 1422 by a connecting arm 1412. The connecting arm 1412 can slide along the guide rail 1422 with the first magnetic collar 141. Preferably, the second and third magnetic collars 143 and 145 are fixedly connected to the base 142 by a connecting arm 1432 and 1452, respectively.

Referring to FIG. 2, a modulation transfer function value measuring apparatus 200 using the above-described modulation transfer function value measuring board 100 according to a second embodiment of the present invention includes a test board 210, a modulation transfer function value measuring board 100, and A drive unit 220. The modulation transfer function value measuring device 200 is for measuring the modulation transfer function value of the lens 300.

The test board 210 has a test pattern, such as black and white stripes.

The modulation transfer function value measuring board 100 includes a substrate 110, an image sensor 120 fixed on the substrate 110, and a vibration sensor 130 mounted on the substrate 110. The image sensor 120 may be a charge coupled image sensor or a complementary metal oxide semiconductor image sensor for sensing a test pattern on the test board 210 via the test lens 300 Imaging on the image sensor 120. The vibration sensor 130 can be a mercury resistance type vibration sensor, and the mercury resistance type vibration sensor can sense whether the substrate 110 has vibration according to a change in the resistance value thereof, for example, the measurement process is to be tested. As soon as the lens 300 contacts the image sensor 120, the resistance value of the mercury resistive vibration sensor 130 changes immediately, indicating that the substrate 110 has vibration. Of course, the change in the resistance value can also reflect the The inclination angle of the substrate 110 with respect to its initial position, and further, the substrate 110 can be restored to the initial position or the like according to the inclination angle.

The modulation transfer function value measuring plate 100 further includes a supporting device 140 for supporting the substrate 110. The support device 140 includes a base 142, a main body 144, a first magnetic collar 141 slidably coupled to the base 142, a second magnetic collar 143 and a third magnetic collar 145. The second and third magnetic collars 143 and 145 are fixedly connected to the base 142 and are disposed on opposite sides of the first magnetic collar 141. The main body 144 passes through the second, first and third magnetic collars 143, 141 and 145 in sequence and is fixedly connected to the first magnetic collar 141. One end 1442 of the main body 144 is a free end, and the other end 1444 is fixedly connected to the substrate 110 of the modulation transfer function value measuring board 100. The magnetic body of the main body 144 between the first, second and third magnetic collars 141, 143 and 145 Maintained in an equilibrium position under the action of force.

The base 142 is generally provided with a guide rail 1422 at a position relative to the first magnetic collar 141. Preferably, the first magnetic collar 141 is movably connected to the guide rail 1422 by a connecting arm 1412. The connecting arm 1412 can slide along the guide rail 1422 with the first magnetic collar 141. Preferably, the second and third magnetic collars 143 and 145 are fixedly connected to the base 142 by a connecting arm 1432 and 1452, respectively.

It can be understood that the second, first and third magnetic collars 143, 141 and 145 can be electromagnets, and the magnetic poles and the magnetic field strength can be adjusted, and the magnetic poles can be SN, NS, SN or NS, SN, NS. The order may be arranged in the order of NS, NS, NS, or SN, SN, and SN, as long as a force balance can be generated between the first, second, and third magnetic collars 141, 143, and 145.

The driving unit 220 can be a motor for driving the to-be-measured lens 300 or the modulation transfer function value measuring board 100, and the measuring lens 300 and the modulation transfer function value measuring board 100 along the to-be-tested lens 300. The direction of the optical axis produces relative movement to achieve optimal imaging of the test pattern on the test panel 210 on the image sensor 120. In this embodiment, the driving unit 220 is configured to drive the to-be-detected lens 300 to move along the optical axis direction of the to-be-detected lens 300 between the modulation transfer function value measuring board 100 and the test board 210.

When the measurement of the to-be-measured lens 300 is performed by using the modulation transfer function value measuring apparatus 200 provided in this embodiment, when the to-be-tested lens 300 is driven by the driving unit 220, the test board 210 and the modulation transfer function value are measured. The plates 100 are moved along the optical axis direction of the lens to be tested 300 so that the test pattern on the test board 210 is optimally imaged on the image sensor 120, when the lens 300 to be tested When the image sensor 120 collides with the image sensor 120, the vibration sensor 130 can sense the vibration of the substrate 110 and the image sensor 120 of the modulation transfer function value measuring board 100. The detector 130 can generate a control signal, such as a signal for controlling the alarm of the alarm or a feedback signal for controlling the change of the resistance value of the mercury, thereby automatically or manually stopping the driving unit 220, and if the lens 300 to be tested and the image sense When the impact force between the detectors 120 is large, the force balance between the first, second, and third magnetic collars 141, 143, and 145 may be broken. At this time, the connection of the first magnetic collar 141 is broken. The arm 1412 can drive the first magnetic collar 141 to slide in the guide rail 1422 of the base 142, thereby driving the main body 144 of the supporting device 140 and the modulation transfer function value measuring plate 100 to slide together, and the lens to be tested 300 and The impact force between the image sensors 120 forms a buffer, Can avoid the entire measuring apparatus 200 and the lens 300 under test serious damage.

Of course, it can be understood that the vibration sensor 130 can also be other devices that can detect vibration, such as a ball vibration switch or a reed switch, etc., as long as the lens to be tested 300 collides with the image sensor 120, It can sense the vibration of the image sensor 120 and the substrate 110, and can generate a control signal to stop the driving unit 220 from operating.

In summary, the present invention has indeed met the requirements of the invention patent, and has filed a patent application according to law. However, the above description is only the preferred embodiment of the present invention, and those skilled in the art will be able to include the equivalent modifications or variations of the present invention in the spirit of the invention. .

100‧‧‧Modulation transfer function value measuring board

110‧‧‧Substrate

120‧‧‧Image sensor

130‧‧‧Vibration sensor

140‧‧‧Support device

141‧‧‧First magnetic collar

1412, 1432, 1452‧‧‧ connecting arms

142‧‧‧Base

1422‧‧‧rail

143‧‧‧Second magnetic collar

144‧‧‧ Subject

1442‧‧‧One of the main bodies

1444‧‧‧The other end of the subject

145‧‧‧ Third magnetic collar

200‧‧‧Modulation transfer function value measuring device

210‧‧‧ test board

220‧‧‧ drive unit

300‧‧‧Special lens

1 is a schematic structural view of a measuring plate provided by a first embodiment of the present invention.

2 is a schematic diagram showing a state of use of a modulation transfer function value measuring apparatus according to a second embodiment of the present invention.

100‧‧‧Modulation transfer function value measuring board

110‧‧‧Substrate

120‧‧‧Image sensor

130‧‧‧Vibration sensor

140‧‧‧Support device

141‧‧‧First magnetic collar

1412, 1432, 1452‧‧‧ connecting arms

142‧‧‧Base

1422‧‧‧rail

143‧‧‧Second magnetic collar

144‧‧‧ Subject

1442‧‧‧One of the main bodies

1444‧‧‧The other end of the subject

145‧‧‧ Third magnetic collar

Claims (8)

A modulation transfer function value measuring plate comprising: a substrate; an image sensor fixed on the substrate; and a vibration sensor mounted on the substrate for sensing the vibration of the substrate; And a support device, the support device includes a base, a main body, a first magnetic collar slidably coupled to the base, a second magnetic collar and a third magnetic collar, the second and third magnetic sleeves The ring is fixedly connected to the base and disposed on opposite sides of the first magnetic collar. The body passes through the second, first and third magnetic collars in sequence and is fixedly connected with the first magnetic collar. The free end, the opposite end is fixedly connected to the substrate, and the main body is maintained in an equilibrium position by the magnetic force between the first, second and third magnetic collars. The modulation transfer function value measuring plate according to claim 1, wherein the image sensor is a charge coupled image sensor or a complementary metal oxide semiconductor image sensor. The modulation transfer function value measuring board according to claim 1, wherein the vibration sensor is a mercury resistance type vibration sensor, a ball vibration switch or a reed switch. A modulation transfer function value measuring device for measuring a modulation transfer function value of a lens to be tested, comprising: a test board having a test pattern; a modulation transfer function value measuring plate, the measuring plate comprising a a substrate and an image sensor fixed on the substrate, the image sensor is configured to sense a test pattern on the test board via the lens to be tested on the image sensor And a driving unit for causing the lens to be tested and the modulation transfer function value measuring plate to move relative to each other along an optical axis direction of the lens to be tested; wherein the modulation transfer function value measuring plate further comprises a loading a vibration sensor disposed on the substrate and a supporting device, when the lens to be tested collides with the image sensor, the vibration sensor can sense the vibration of the substrate and generate a control signal to drive The unit stops working; the supporting device includes a base, a main body, a first magnetic collar slidably coupled to the base, a second magnetic collar and a third magnetic collar, the second and third magnetic collars Fixedly connected to the base and disposed on opposite sides of the first magnetic collar, the body sequentially passes through the second, first and third magnetic collars and is fixedly connected with the first magnetic collar, one end of which is The free end and the opposite end are fixedly connected to the substrate, and the main body is maintained in an equilibrium position by the magnetic force between the first, second and third magnetic collars. The modulation transfer function value measuring device according to claim 4, wherein the image sensor is a charge coupled image sensor or a complementary metal oxide semiconductor image sensor. The modulation transfer function value measuring device according to the fourth or fifth aspect of the invention, wherein the vibration sensor is a mercury resistance type vibration sensor, when the lens to be tested collides with the image sensor, The mercury resistive vibration sensor is capable of sensing an angle of inclination of the substrate relative to an initial position thereof. The modulation transfer function value measuring device according to claim 4, wherein the test pattern is black and white stripes. The modulation transfer function value measuring device according to claim 4, wherein the driving unit is a motor.