Camera and distance measuring apparatus used in the same

• US 6,792,203 B1
• Filed: 08/30/2000
• Issued: 09/14/2004
• Est. Priority Date: 09/01/1999
• Status: Expired due to Term

• Current Assignee: OM Digital Solutions Corporation
• Original Assignee: Olympus Optical Company Ltd. (Olympus Corporation)
• Inventors: Ide, Masataka, Nonaka, Osamu
• Primary Examiner(s): Gray, David M.
• Assistant Examiner(s): BLACKMAN, ROCHELLE ANN J
• Application Number:
  US09/651,877
• Time in Patent Office: 1,476 Days
• Field of Search: 396/65, 396/69, 396/106, 396/121, 396/122, 396/123, 396/157, 396/233, 396/234
• US Class Current: 396/65
• CPC Class Codes: G01S 17/48 Active triangulation systems, i.e. using the transmission and reflection of electromagnetic waves other than radio waves
• CPC Class Codes: G01S 17/89 for mapping or imaging

Abstract

In a camera a pickup element images an object image. An A/D converter A/D converts an output of the pickup element. A processing section includes a night scene judging section for judging whether or not the scene to be photographed is the night scene on the basis of a digital image signal output from the A/D converter. In a distance measuring apparatus of the camera. An area sensor is used for an auto-focus. A first judging section judges that the scene to be photographed is a night scene on the basis of an output of the area sensor. In the case where the first judging section judges that the photography scene is not the night scene, a second judging section judges whether or not the scene to be photographed is the reverse light scene. A main object specifying section specifies the main object in the case where either the first judging section or the second judging section judges the scene to be photographed is either the night scene or the reverse light scene. A distance measuring section conducts distance measuring calculation with respect to the main object specified by the main object specifying section.

Claims

1. A camera comprising:

a pickup element;

a judging section for judging whether or not a scene to be photographed is a night scene on the basis of an average luminance value and luminance distribution of a whole photographing screen obtained from an output of the pickup element, the judging section judging the scene being the night scene in a case where the average luminance value of the whole photographing screen is lower than a predetermined value and the high luminance area is dotted within the photographing screen; and

a setting section for setting a photographing mode in accordance with a judging result of the judging section.

2. The camera according to claim 1, further comprising:

a strobe light emitting portion for previously emitting light in a case where the judging section judges that the scene to be photographed is the night scene; and

a distance measuring section which conducts a distance measuring calculation with respect to an area in which a difference between the sensor data at a time of a previous light emission integration and the sensor data at a time of integration without the previous light emission is not less than the predetermined value.

3. The camera according to claim 2, wherein the setting section sets the photographing mode to the night scene portrait mode in a case where the distance measuring section obtains a calculation result such that the distance of the object is in the short distance, and sets the photographing mode to the normal night scene mode in a case where the distance measuring section obtains the calculation result such that the distance of the object is not in the short distance.

4. The camera according to claim 1, wherein the judging section judges that the scene to be photographed is the night scene in a case where the average luminance value of the whole photographing screen is lower than the predetermined value, a first area number in which pixels having a higher luminance than the predetermined value continue is larger than a predetermined number, and a second area number in which pixels having a lower luminance than the predetermined value continue is smaller than the predetermined number.

5. The camera according to claim 1, wherein the judging section judges the scene with respect to the number of pixels having a higher luminance than a predetermined value, and the number of pixels having a medium luminance, and the number of pixel having a lower luminance of the distance measurement area corresponding to the whole photographing screen.

6. The camera according to claim 5, wherein the judging section judges that the scene is the night scene in a case where, in the distance measurement area corresponding to the whole photographing screen, both of the number of pixels having the higher luminance than the predetermined value and the number of pixels having the lower luminance than the predetermined value are larger than the predetermined number, and the number of pixels having a medium luminance is smaller than the predetermined number.

7. The camera according to claim 6, further comprising:

a strobe light emitting portion which conducts a previous light emission in a case where the judging section judges that the scene to be photographed is the night scene;

a detection section which detects an area where the number of pixels having the medium luminance is counted and increased on the basis of data at a time of a previous light emission integration;

a distance measuring section which conducts a distance-measuring calculation with respect to an area where the pixel having the medium luminance detected with the detection section is increased.

8. The camera according to claim 7, wherein the setting section switches the photographing modes in accordance with a calculation result of the distance measuring obtained from the distance measuring section.

9. The camera according to claim 8, wherein the setting section conducts the strobe light emission so that the main object is subjected to an appropriate exposure, and sets the photographing mode to a night scene portrait mode for prolonging exposure time so that the background is also subjected to an appropriate exposure, in a case where the distance measuring section obtains a calculation result that the main objects is located in the short distance.

10. The camera according to claim 8, wherein the setting section does not conduct a strobe light emission, and sets the photographing mode to a normal night scene mode for prolonging the exposure time so that the background is subjected to an appropriate exposure, in a case where the distance measuring section obtains a calculation result that the main object is not located in the short distance.

11. A camera comprising:

a pickup element;

a judging section for judging whether or not a scene to be photographed is a night scene on the basis of an average luminance value and luminance distribution of a whole photographing screen obtained from an output of the pickup element, the judging section judging the scene not being the night scene in a case where the average luminance value of the whole photographing screen is higher than a predetermined value, or in a case where the high luminance area is not dotted in the photographing screen; and

a setting section for setting a photographing mode in accordance with a judging result of the judging section.

12. The camera according to claim 11, wherein the judging section judges that the scene to be photographed is not the night scene in a case where the average luminance value of the whole photographing screen is higher than the predetermined value, or a first area number in which pixels having a higher luminance than the predetermined value continue is smaller than a predetermined number, or a second area number in which pixels having a lower luminance than the predetermined value continue is larger than the predetermined number.

13. A distance measuring apparatus of a camera comprising:

a pickup element;

a luminance distribution calculation section which calculates a luminance distribution within a photographing screen on the basis of an output of the pickup element;

a continuous region detection section which detects a region where the luminance within a predetermined range continues on the basis of an output of the luminance distribution calculation section; and

a main object specifying section which specifies a main object on the basis of the configuration of the area where the luminance within the predetermined range continues.

14. A distance measuring apparatus of a camera comprising:

a strobe light emitting portion;

an area sensor to be used for an auto-focus which conducts an integration operation at a time of a previous light emission;

a first judging section for judging whether or not a scene to be photographed is a night scene on the basis of an output of the area sensor;

a second judging section which judges whether or not the scene to be photographed is a reverse light scene in a case where judgment is made that the scene to be photographed is not the night scene;

a main object specifying section which specifies the main object, wherein

the main object specifying section specifies the main object in a case where a differential data between a sensor data of the area sensor at a time of integration with the previous light emission and a sensor data at a time of integration without the previous light emission is not less than a predetermined value when the first judging section judges that the scene to be photographed is the night scene, and

the main object specifying section specifies the main object in a case where differential data between the sensor data of the area sensor at the time of integration with the previous light emission and the sensor data at the time of integration without the previous light emission is not less than the predetermined value when the second judging section judges that the scene to be photographed is reverse light scene; and

a distance measurement calculation section which calculates a distance measurement with respect to the main object which is specified with the main object specifying section.

15. The distance measuring apparatus according to claim 14, wherein the main object specifying section includes:

an average luminance value calculation section for calculating the average luminance value of the photographing screen on the basis of the output of the area sensor;

an area calculation section for extracting continuous luminance data within the predetermined range and calculating the square measurement of the extracted luminance data in the case where the average luminance value is higher than the predetermined value;

an area judging section for judging whether or not an area of the extracted area calculated with the area calculation section is larger than a predetermined value;

a configuration judging section for judging the configuration of the extracted area in the case where the area of the extracted area is not less than the predetermined value with the square measurement judging section; and

an image width calculation section for calculating the image width in a vertical direction of the extracted area.

16. The distance measuring apparatus according to claim 15, wherein the configuration judging section judges whether or not the configuration of the extracted area is approximately circular.

17. The distance measuring apparatus according to claim 16, wherein the image width calculation section calculates the image width of the extracted area in the case where the configuration judging section judges that the configuration of the extracted area is approximately circular.

18. The distance measuring apparatus according to claim 17, wherein the main object specifying section specifies the presence of the main object in the extracted area in the case where the image width calculated with the image width calculation section is within the predetermined range.

19. The distance measuring apparatus according to claim 18, wherein the distance measuring section conducts distance measuring calculation with respect to the approximately circular area with which the main object specifying section specifies the presence of the main object.

20. The distance measuring apparatus according to claim 19, wherein the photographing screen is set to the reverse light scene after the distance measuring calculation by the distance measuring section.

21. The distance measuring apparatus according to claim 16, wherein the configuration judging section judges whether or not the configuration is approximately rectangular in the case where the configuration judging section judges that the configuration is not approximately circular.

22. The distance measuring apparatus according to claim 21, wherein the image width calculation section calculates the image width of the extracted area in the case where the configuration judging section judges that the configuration of the extracted area is approximately rectangular.

23. The distance measuring apparatus according to claim 22, wherein the main object specifying section specifies the presence of the main object in the extracted area in the case where the image width calculated with the image width calculation section is within the image width range.

24. The distance measuring apparatus according to claim 23, wherein the distance measuring section conducts the distance measuring calculation with respect to the approximately rectangular area with which the presence of the main object is specified with the main object specifying section.